An integrative revision of the genus Isognathotermes (Termitidae: Cubitermitinae) with description of seven new species and four new subspecies

1 European Journal of Taxonomy 1024: 1–197 https://doi.org/10.5852/ejt.2025.1024.3099 europeanjournaloftaxonomy.eu ISSN 2118-9773 2025 · Josens G. et al. This work is licensed under a Creative Commons Attribution License (CC BY 4.0) Received: 27 July 2024 • Accepted: 18 July 2025 • Published: 5 November 2025 Topic editor: Tony Robillard • Section editor: Frédéric Legendre • Desk editor: Kristiaan Hoedemakers Monograph urn:lsid:zoobank.org:pub:2A22C9AF-0E2D-46D1-A086-6CBE166F0A77 An integrative revision of the genus Isognathotermes (Termitidae: Cubitermitinae) with description of seven new species and four new subspecies Guy JOSENS 1,* , Jean DELIGNE 2 , Myriam HARRY 3 , Virginie ROY 4  , Pierre D. AKAMA 5 , Tenon COULIBALY 6 , Kanvaly DOSSO 7 , Georg GOERGEN 8 , Michel HASSON 9 , Patrick KASANGIJ A KASANGIJ10 , Carmel KIFUKIETO 11 , Bruno LE RU 12 , Laura Estelle Yêyinou LOKO 13   , Abdoulaye Baila NDIAYE 14  , Yves ROISIN 15 , Noémie SION 16 , Jan ŠOBOTNIK 17 , Petr STIBLIK 18 , Soki KUE DI KUENDA 19 , Saran TRAORÉ 20 , Manuela VIAGE 21 , Solange Patricia WANGO 22 , Esra KAYMAK 23 , Thomas BOURGUIGNON 24  & Simon HELLEMANS 25,* 1,2,16 Université Libre de Bruxelles, Département de Biologie des Organismes, Écologie végétale et Biogéochimie, Av. Roosevelt 50 - cp 244, 1050 Brussels, Belgium. 2 Royal Museum for Central Africa, Entomology, Leuvensesteenweg 13, 3080 Tervuren, Belgium. 3 UMR EGCE (Evolution, Génomes, Comportement, Evolution), Université Paris-Saclay - CNRS - IRD, Bat IDEEV, 12 route 128, Gif-sur-Yvette, France. 4 Univ Paris Est Créteil, Sorbonne Université, Université Paris-Cité, CNRS, IRD, INRAE, Institut d’écologie et des sciences de l’environnement, IEES, F-94010 Créteil, France. 5 Université de Yaoundé 1, Cameroon. 6 Université Peleforo Gon Coulibaly, Côte d’Ivoire. 7 Université Nangui Abrogoua, Côte d’Ivoire. 8 International Institute of Tropical Agriculture, 08 BP 0932 Tri Postal, Cotonou, Benin. 9 Royal Museum for Central Africa, Ornithology, Leuvensesteenweg 13, 3080 Tervuren, Belgium. 10 Université de Lubumbashi, DRC. 11 Université de Kinshasa, DRC. 12 Laboratoire Evolution Génomes Comportement et Ecologie, UMR CNRS 9191, IRD 247 and Université Paris Sud, Université Paris-Saclay, France. 13 Université Nationale des Sciences, Technologies, Ingénierie et Mathématiques (UNSTIM), BP 486 Abomey, Sogbo-Aliho, Benin. 14 Institut fondamental d’Afrique noire (IFAN), Université Cheikh Anta Diop de Dakar, Senegal. 15 Evolutionary Biology and Ecology, Université Libre de Bruxelles, Belgium. 17 Czech University of Life Sciences, Czech Republic, and Biology Centre, Czech Academy of Sciences,InstituteofEntomology,ČeskéBudějovice,CzechRepublic. 18 Czech University of Life Sciences, Czech Republic. 19,21 Universidade Agostinho Neto, Angola. 20 Université Nazi Boni, Burkina Faso. European Journal of Taxonomy 1024: 1–197 (2025) 2 22 Université de Bangui, Central African Republic. 23,24,25 Okinawa Institute of Science and Technology, Japan. * Corresponding authors: guy[email protected], for the molecular part: [email protected] 2 Email: [email protected] 3 Email: [email protected] 4 Email: [email protected] 5 Email: [email protected] 6 Email: [email protected] 7 Email: [email protected] 8 Email: [email protected] 9 Email: [email protected] 10 Email: [email protected] 11 Email: [email protected] 12 Email: [email protected] 13 Email: [email protected] 14 Email: [email protected] 15 Email: Y[email protected] 16 Email: [email protected] 17 Email: [email protected] 18 Email: petr[email protected] 19 Email: [email protected] 20 Email: [email protected] 21 Email: [email protected] 22 Email: [email protected] 23 Email: [email protected] 24 Email: Thomas.Bour[email protected] Table of contents Abstract ................................................................................................................................................... 3 Introduction ............................................................................................................................................. 4 Material and methods .............................................................................................................................. 5 Results ....................................................................................................................................................11 Genus Isognathotermes Sjöstedt, 1926 ...............................................................................................11 Identificationkey.................................................................................................................................36 Valid species and subspecies ................................................................................................................39 I. acristatus Josens & Deligne sp. nov. ............................................................................................39 I. bulbifrons (Sjöstedt, 1924) ...........................................................................................................43 I.finitimus (Schmitz, 1916) .............................................................................................................56 I. fungifaber (Sjöstedt, 1896) ...........................................................................................................66 I. magniplanifrons Josens & Deligne sp. nov. .................................................................................81 I. minitabundus (Sjöstedt, 1913) ......................................................................................................87 I. modicus Josens & Deligne sp. nov. ..............................................................................................95 I. phallicaecalis Josens & Deligne sp. nov. ........................................................................................99 I. phalloides Josens & Deligne sp. nov. .........................................................................................104 I. planifrons (Sjöstedt, 1924) .........................................................................................................112 I. rectimalatus Josens & Deligne sp. nov. ......................................................................................122 I. severus (Silvestri, 1914) .............................................................................................................127 I.similifinitimus Josens & Deligne sp. nov. .....................................................................................139 I. ugandensis (Fuller, 1923) ..............................................................................................................144 JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 3 I. ugandensis ugandensis Josens & Deligne subsp. nov. ............................................................... 152 I. ugandensis burundii Josens & Deligne subsp. nov. .................................................................. 156 I. ugandensis kenyae Josens & Deligne subsp. nov. ..................................................................... 158 I. ugandensis malawii Josens & Deligne subsp. nov. ................................................................... 160 I. zenkeri (Desneux, 1904) ............................................................................................................ 161 Incertae sedis, species inquirenda .................................................................................................... 167 I. bredoi (nomen nudum) .............................................................................................................. 167 I. congoensis (Emerson, 1928) ..................................................................................................... 168 I. aff. planifrons (undescribed) ..................................................................................................... 171 Unknown Isognathotermes from Malawi (undescribed) .............................................................. 172 Junior synonyms..............................................................................................................................172 I. antennalis (Sjöstedt, 1924) junior synonym of I. ugandensis ugandensis ..........................172 I. banksi (Emerson, 1928) junior synonym of I. fungifaber ....................................................173 I. comstocki (Emerson, 1928) junior synonym of I. fungifaber ................................................174 I. fungifaber var. elongata (Sjöstedt, 1924) junior synonym of I. planifrons ............................175 I. gaigei (Emerson, 1928) junior synonym of I. planifrons ......................................................176 I. gibbifrons (Sjöstedt, 1924) junior synonym of I. bulbifrons ..................................................177 I. heghi (Sjöstedt, 1924) junior synonym of I. bulbifrons .........................................................178 I. kemneri (Emerson, 1928) junior synonym of I. bulbifrons ....................................................179 I. loubetsiensis (Sjöstedt, 1924) junior synonym of I. planifrons ...........................................180 I. modestior (Silvestri, 1914) junior synonym of I. severus ..................................181 I. schmidti (Emerson, 1928) junior synonym of I. fungifaber ....................................................181 I. silvestrii (Sjöstedt, 1925) junior synonym of I. severus .......................................................182 I. speciosus (Sjöstedt, 1924) junior synonym of I.finitimus .....................................................183 I. subarquatus (Sjöstedt, 1926) junior synonym of I.finitimus .................................................184 Discussion ........................................................................................................................................... 185 Nomenclatural changes made in this work ......................................................................................... 189 Acknowledgements ............................................................................................................................. 190 Data availability statement .................................................................................................................. 190 Author's contributions ......................................................................................................................... 190 Conflictofinterestdeclaration ............................................................................................................ 191 References ........................................................................................................................................... 191 Abstract. Cubitermitinae species whose workers have enteric valves of the fungifaber and finitimus patterns were previously gathered into the genus Isognathotermes. Here, we revise this genus, combining the morphological and anatomical features of all castes, as well as the species’ chorological, ecological, and phylogenetic (mitogenome) characteristics in an integrative taxonomic approach. In addition to the genetic signature, the best morphological criteria for generic recognition are found in the workers’ EVA (enteric valve architecture) and the spinosity of the fore coxae of the workers, and the best criteria for specific recognition are found in (a) the valve and caecum of the workers, (b) the caecum, dimensions of the head, and curvature of the mandibles of the soldiers, and (c) the dimensions of the head and the relative dimensions of eyes and ocelli of the imagines. After revision, only eight of the 22 known taxa remain valid, 14 known taxa become junior synonyms, and one is considered as incertae sedis; six new morphologically recognizable species, one cryptic species and four new subspecies are described. The mitogenome of 12 out of the 15 valid species have been sequenced. The following described species are considered valid: I. bulbifrons (Sjöstedt, 1924), I.finitimus (Schmitz, 1916), I. fungifaber (Sjöstedt, 1896), I. minitabundus (Sjöstedt, 1913), I. planifrons (Sjöstedt, 1924), I. severus (Silvestri, 1914), I. ugandensis (Fuller, 1923) and I. zenkeri (Desneux, 1904). The following species are described as new: I. acristatus Josens & Deligne sp. nov., I. modicus Josens & Deligne sp. nov., I. magniplanifrons Josens & Deligne sp. nov., I. phallicaecalis Josens & Deligne sp. nov., I. phalloides Josens & Deligne European Journal of Taxonomy 1024: 1–197 (2025) 4 sp. nov., I. rectimalatus Josens & Deligne sp. nov., and I.similifinitimus Josens & Deligne sp. nov. Four new subspecies of I. ugandensis are recognized: I. ugandensis burundii Josens & Deligne subsp. nov., I. ugandensis kenyae Josens & Deligne subsp. nov., I. ugandensis malawii Josens & Deligne subsp. nov., and I. ugandensis ugandensis Josens & Deligne subsp. nov. The following species are considered junior synonyms: I. antennalis (Sjöstedt, 1924), I. banksi (Emerson, 1928), I. comstocki (Emerson, 1928), I. fungifaber var. elongata (Sjöstedt, 1924), I. gaigei (Emerson, 1928), I. gibbifrons (Sjöstedt, 1924), I. heghi (Sjöstedt, 1924), I. kemneri (Emerson, 1928), I. loubetsiensis (Sjöstedt, 1924), I. modestior (Silvestri, 1914), I. schmidti (Emerson, 1928), I. silvestrii (Sjöstedt, 1925), I. speciosus (Sjöstedt, 1924), and I. subarquatus (Sjöstedt, 1926). Are considered as incertae sedis: I. bredoi (nomen nudum), I. congoensis (Emerson, 1928), an “I. aff. planifrons” (undescribed), and an unknown Isognathotermes from Malawi (undescribed). GenBank accessions: see Supp.file3 and ‘Material examined’ of each chapter. Keywords. Blattodea, Blattaria, Isoptera, Cubitermes, cryptic species, integrative taxonomy, chorology, DNA barcoding, species delimitation. Josens G., Deligne J., Harry M., Roy V., Akama P.D., Coulibaly T., Dosso K., Goergen G., Hasson M., Kasangij a Kasangij P., Kifukieto C., Le Ru B., Loko L.E.Y., Ndiaye A.B., Roisin Y., Sion N., Šobotnik J., Stiblik P., Kue di Kuenda S., Traoré S., Viage M., Wango S.P., Kaymak E., Bourguignon T. & Hellemans S. 2025. An integrative revision of the genus Isognathotermes (Termitidae: Cubitermitinae) with description of seven new species and four new subspecies. European Journal of Taxonomy 1024: 1–197. https://doi.org/10.5852/ejt.2025.1024.3099 Introduction The emblematic Cubitermes Wasmann, 1906 is widespread in Africa, and was composed, in 2013, of 67 taxa (Krishna et al. 2013: 1912). In most cases, the original descriptions were rather succinct and insufficientfordelimitingthespeciesclearly.SothatEmerson(1928:507)alreadyemphasizedonthe difficultyofidentifyingCubitermesspecies;thisdifficultyresultedfromthemorphologicalproximity amongspeciesandfromhighintraspecificvariability,whichwerebothignoredbypriortermitologists such as Sjöstedt (1896–1926), Silvestri (1914) or Fuller (1923). Ruelle (1992) reiterated the need to revise the genus Cubitermes and drew attention to the fact that many species had been forgotten, i.e., they had been described but not reported since. More recently, other authors noted a great diversity among members of Cubitermes, which suggested it may be composed of several distinct lineages. Bouillon & Vincke (1971) suggested that Cubitermes should be split into at least three genera based on their enteric valves. This proposal was subsequently supported by the observation that species of Cubitermes can coexist in the same habitat but when this happens, the coexisting species exhibit different enteric valves, probably linked to competition and the food niche (Wango & Josens 2011). Not only the enteric valve but also the proctodeal blind diverticulum or caecum on the paunch of the hindgut has various morphologies, and provides clues to specificrecognition(Johnson1979).Thisblindcaecumhassincebeenfoundtobeacharacteristicof the Cubitermitinae subfamily (Krishna et al.2013:123).Inhisreferenceworkontheidentificationof termite workers, Sands (1998) also put forward the diversity of both enteric valve armatures and caecum shapes, but did not suggest splitting the genus Cubitermes. Most Cubitermes nests are mushroom-shaped (with some variations) in West and Central Africa, which has been interpreted as a rain protection device (Emerson 1938); in accordance, the nests are generally dome-shaped (uncapped) in drier East Africa. As already mentioned by Williams (1966), the shape of thenestsdoesnotprovideanyidentificationcriterionbutratherseemstobeinfluencedbyenvironmental conditions (Wango & Josens 2011). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 5 Facedwiththedifficultyofdistinguishingspeciesbyambiguousmorphologicaldiagnoses,Royet al. (2006) showed the value of mitochondrial and nuclear markers for distinguishing sympatric Cubitermes species. Recent works subdivided the genus Cubitermes into nine species groups on basis of their enteric valve architectures (EVAs; Josens & Deligne 2019); and phylogenetic studies evidenced that Cubitermes was paraphyletic with respect to Apilitermes, Crenetermes, Megagnathotermes and Thoracotermes (Bourguignon et al. 2017; Hellemans et al. 2021). Hellemans et al.(2021)recognizedfiveclades,inline withtheEVAsoftheninegroups.Thesefivecladeswereerectedthereinintofivegenera:Cubitermes Wasmann, 1906, Ternicubitermes Josens & Deligne, 2021, Isognathotermes Sjöstedt, 1926, Nitiditermes Emerson, 1960, and Polyspathotermes Josens & Deligne, 2021. However,whiletheboundariesbetweenthesefivegeneraarenowwell-defined,speciesidentification remains arduous. The restored genus Isognathotermes grouped species whose workers have enteric valves of the fungifaber and finitimus patterns (Josens & Deligne 2019) and included, when restored, 15 species (Hellemans et al. 2021: table S4), and currently contains 15 valid species found from Gambia to Malawi. The aims of this article are to revise the genus Isognathotermes and to delineate the species by means of an integrative approach, i.e., to describe or re-describe the species based on the morphology and anatomy of imagines, soldiers, and workers, combined, when possible, with molecular and chorologic-ecological data,andtoprovideanidentificationkey. Material and methods Abbreviations Museum abbreviations AMNH = American Museum of Natural History, New York, the United States IEAP = Instituto di Entomologia Agraria, Portici (Napoli), Italy MCGD = Museo Civico di Storia Naturale “Giacomo Doria”, Genoa, Italy MNHN = Muséum national d’Histoire naturelle, Paris, France MURS = Museo Università di Roma “Sapienza”, Roma, Italy NHMM = Natuurhistorisch Museum of Maastricht, the Netherlands NHMUK = Natural History Museum, London, the United Kingdom NHRM = Naturhistoriska Riksmuseet, Stockholm, Sweden PPRI = Plant Protection Research Institute, Biosystematics Division, Queenswood, Pretoria, South Africa RBINS = Royal Belgian Institute of Natural Sciences, Brussels, Belgium RMCA = Royal Museum for Central Africa, Tervuren, Belgium, including A. Bouillon’s collection UMMZ = Museum of Zoology, University of Michigan, Ann Arbor Country abbreviations CAR = Central African Republic DRC = Democratic Republic of the Congo (Kinshasa) RCI = Republic of Côte d’Ivoire Morphological abbreviations aff. =affinis,ataxonthathasasimilarmorphology C1–C8 = colour abbreviations from C1 (very pale yellow) to C8 (almost dark)   (Josens&Deligne2019:5,fig.1) Cd = deep colour Cf = faded colour DJ = labelling marker of the morphological study European Journal of Taxonomy 1024: 1–197 (2025) 6 EVA = enteric valve architecture IEyD =imago,eyelargerdiameter(Josens&Deligne2019:14,fig.6b) IEyd =imago,eyelesserdiameter(Josens&Deligne2019:14,fig.6b) IEyD/IEyd = imago, compound eye elongation index (= eye index in Williams 1966) equals 1 if the eye is circular and increases when it becomes more oval IEyD/IHdW = imago, oculo-cephalic index, it increases when the compound eye becomes larger relative to the head IHdW =imago,headwidthacrosscompoundeyes(Josens&Deligne2019:14,fig.6a) IMlAmD =imago,leftmandibleapicaltofirstmarginaldistance(betweentips)(similar to WMlAmD, Josens & Deligne 2019: 20,fig.8b) IMlmmD =imago, left mandible distance between the first and third marginal tips (similar to WMlmmD, Josens & Deligne 2019: 20,fig.8b) IMlAmD/IMlmmD = Imago; left mandibular apico-marginal index (= La/L1 in Sands 1972); it increases when the apical tooth of the left mandible becomes longer   withrespecttothedistancebetweenthefirstandthirdmarginalteeth IOcD =imago,ocelluslargerdiameter(Josens&Deligne2019:14,fig.6d) IOcd =imago,ocelluslesserdiameter(Josens&Deligne2019:14,fig.6d) IOcD/IOcd = imago, ocellus elongation index, equals 1 if the ocellus is circular and increases when it becomes more oval IPcW =imago,posclypeuswidth(Josens&Deligne2019:14,fig.6b) IPnW =imago,pronotumwidth(Josens&Deligne2019:14,fig.6c) IT3L = imago, length of the left hind tibia (similar to ST3L, Josens & Deligne   2019:16,fig.7i) IWgL =imago,leftfore-winglengthtosuture,(Josens&Deligne2019:14,fig.6e) PC = primary cushion of the enteric valve SC = secondary cushion of the enteric valve SHdC =soldier,sagittaofheadupperconcavity(Josens&Deligne2019:16,fig.7b)   (equalszeroiftheupperprofileiseitherstraightorslightlyconvex) 100 * SHdC/SHdL = soldier, percentage of upper head concavity SHdL = soldier, head length to the fore margin of the clypeus (Josens & Deligne   2019:16,fig.7a) SHdW =soldier,headwidth(Josens&Deligne2019:16,fig.7a) SHdL/SHdW = soldier, head elongation index SMlC = soldier, left mandible larger curvature (or sagitta of apico-molar arc); greatest distance between the inner edge of the blade and a line tangent to the tip of apical tooth and to the margin of the molar tooth (Josens &   Deligne2019:16,fig.7f) SMlc = soldier, left mandible lesser curvature (or sagitta of apico-marginal arc)   betweenthemarginaltoothandtheapicaltip(Josens&Deligne2019:16,fig.7f) SMlC/SMlc = soldier, left mandible bi-curvature index, it increases mainly when the molar tooth becomes more prominent SMlc/SMlL = soldier, left mandible apical curvature index, it increases when the mandible becomes more curved; this is not the same curvature index as in Williams (1966) SMlc/SMrc = soldier, ratio between the left and right mandible lesser curvatures, the more asymmetrical the mandibles, the greater the deviation from 1 SMldR = soldier, radius of the circle of the distal mandible quarter (Josens & Deligne   2019:16,fig.7h) SMlL = soldier, left mandible length in ventral view; from apical tip to base of   condyle(Josens&Deligne2019:16,fig.7f),thisisnotthesamemeasure as in Williams (1966) JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 7 SMlL/SHdL = soldier, gnatho-cephalic index, it increases when the mandible becomes longer with respect to head length SMlpR = soldier, radius of the circle of the proximal mandible half (Josens & Deligne   2019:16,fig.7h) ln(SMlpR) - ln(SMldR) = soldier, (acceleration of the mandible curvature), it increases if the mandible becomes more curved distally with respect to the proximal curvature and it would equal zero if the mandible blade was a section of a circle (same proximal and distal radii) SMlW = soldier, width of the mandible precisely at mid-distance between the   marginalandtheapicaltips(Josens&Deligne2019:16,fig.7g) SMlW/SMlL = soldier, left mandible robustness index, it increases if the mandible becomes thicker in relation to its length SMrC = soldier, right mandible larger curvature (or sagitta of apico-molar arc); greatest distance between the inner edge of the blade and a line tangent to the tip of apical tooth and to the margin of the molar tooth (Josens &   Deligne2019:16,fig.7f) SMrc = soldier, right mandible lesser curvature (or sagitta of apico-marginal arc)   betweenthemarginaltoothandtheapicaltip(Josens&Deligne2019:16,fig.7f) ST3L =soldier,lengthofthelefthindtibia(Josens&Deligne2019:16,fig.7i) WHdW =worker,headmaximalwidth(Josens&Deligne2019:20,fig.8a) WMlAmD =worker, left mandible apical to first marginal distance (between tips)   (Josens&Deligne2019:20,fig.8b) WMlL =worker,functionallengthofleftmandible(Josens&Deligne2019:20,fig.8c) WT3L =worker,lengthofthelefthindtibia(similartoJosens&Deligne2019:16,fig.7i) WVP1-bil = worker’s valve PC1-bilaterality index=the ratio of WVP1L length over the average length of the two other odd cushions (WVP3L and WVP5L) WVP-AvL = worker, enteric valve, average length of the primary cushions 1 to 6 WVP-AvW = worker, enteric valve, average width of the primary cushions 1 to 6 WVPOdd-Elg = worker’s valve odd PCs elongation index; it is calculated as the average length of the odd cushions (WVP1L, WVP3L and WVP5L) on the average width of the same odd cushions (WVP1W, WVP3W and WVP5W); it measures the narrowness of the odd PCs WVS-AvL = worker, enteric valve, average length of the secondary cushions 12 to 61 WVS-AvW = worker, enteric valve, average width of the secondary cushions 12 to 61 Morphology A total of 752 samples were studied, 421 in a full study and 331 in a partial study. Full study SampleswereobservedwithaZeissDiscoveryV12stereoscopicmicroscope(magnification8–100×) and photographed with an ICc3 camera (3 million pixels resolution). The photographs were taken in extended focus driven by the AxioVision® 4.8 (Zeiss) software. In most cases, the samples were oriented accordingtoastandardisedprocedure:thesamplewasslightlysunkintoabedoffineglassbeads (GlaskügelchenbyKremerPigmenteGmbH,150–210μm)andorientatedsothattwoormorepoints were simultaneously in focus in order to make subsequent measurements comparable. The morphological study is based on three series of standardised photos (one series per caste) supplementedbyindicesdesignedtoreflectmorphologyasobjectivelyaspossible. After several Regression Analyses, Principal Component Analyses and Stepwise Variable Selections (in Factorial Discriminative Analyses) with the software R, packages ade4 (Chessel et al. 2004), FactoMineR European Journal of Taxonomy 1024: 1–197 (2025) 8 and klaR, 29 variables and eight indices were selected for the imagines, 36 variables and 16 indices for the soldiers, 50 variables and 14 indices for the workers’ morphology (including their EVAs). Standardisation of photos and coding of variables were fully described and illustrated in Josens & Deligne (2019: 5–22); the same terminologies and abbreviations have also been used for colour, setation, antennae, mandibles, and EVAs. The samples studied following this “full study procedure” received a study code: “DJ NNNN” where ‘NNNN’ is a four-digit number. Full study was performed until a total of at least 20 samples for a given species was reached; extra material was then studied following a simplifiedprocedure(hereunder). Toproducethefigures,thephotographsweretracedontracingpaperappliedtothescreenofacomputer. Partial study(simplifiedprocedure) Three photographs of the soldiers were taken: head capsule in dorsal view, head capsule in lateral view and mandibles in ventral view, not detached from head. These photos allowed to perform a limited series of measurements: SHdC, SHdL, SHdW, SMlc, SMldR, SMlpR,SMlW,andcalculatefiveindices:ln(SMlpR)/ln(SMldR),SHdL/SHdW,SMlc/SMlL,SMlL/ SHdL and SMlW/SMlL. If imagines were present, they were nevertheless studied following the full study procedure. Workers were not photographed but one individual was dissected, and its caecum and enteric valve checked (and frequently photographed). The samples studied following the partial study procedure received a study code: “DJ XNNN” where ‘X’ is a letter and ‘NNN’ a three-digit number. Data analyses Becauseofthegreatintraspecificvariability,PrincipalComponentAnalysis(PCA)hasprovedtobea more effective tool for grouping samples by species than other analyses such as Hierarchical Cluster Analysis. The analyses were carried out using the ‘ade4’ package (Chessel et al. 2004) of the R language (R Core Team 2018). PCAs were performed throughout the study with progressively increasing numbers of samples: some PCAs were carried out on all the available data (752 samples at the end of the study): 278 imagines, 734 soldiersand400workersbutthesefigureswereoftendifficulttounderstand,asshowninFig. 20. To increase the discrimination capacity, most of the PCAs were carried out by distinguishing species with a fungifaber EVA (178 imagines, 424 soldiers and 221 workers) and species with a finitimus EVA (100 imagines, 310 soldiers and 179 workers) as shown in Figs 21–22. Chorological and ecological data As far as possible, species are characterised by their geographical distribution or chorology: for this we refertotheecoregionsdefinedfortheWWFthatincludeclimate,soilandvegetationtypes(Olsonet al. 2001; Burgess et al. 2006). However, for some old samples with partial labelling, their chorology had to be deduced or assumed from the collectors’ travel records. A few, rare unlabelled samples were excluded from our study because they could not be attributed to any ecoregion. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 9 Where possible, we have checked that the species’ geographical range is not fragmented: see “Species delimitation”. The maps were produced with the package ‘maps’ and ‘mapdata’ of the R language (R Core Team 2018). Molecular data Extraction and sequencing For mitogenome analyses, DNA extraction was attempted on 210 specimens, either sourced from museum collections or newly collected samples. (i) For museum material, preserved for a long time in 70–80% alcohol, samples consisted of either full individuals or dissection residuals. They were extracted using a non-destructive DNA extraction protocol for ancient DNA (Gilbert et al. 2007; Thomsen et al. 2009), with tissues incubating in the digestion buffer for 20 hours. (ii) Additional new material was preserved in either 80% ethanol or RNA-later©. For these samples, DNA extraction was performed on full individuals using the DNeasy Blood & Tissue extraction kit (Qiagen). In total, 104 specimens produced usable sequencing data. Across the 104 new mitogenomes submitted herewith, 91 mitogenomes were composed of at least 14 865 bp, six were between 10 000 and 14 865 bp, and seven were below 10 000 bp (Supp.file3). Libraries were prepared using the NEBNextâ Ultra™ II FS DNA Library Preparation Kit (New England Biolabs) and the Unique Dual Indexing Kit (New England Biolabs). The reagent volumes were reduced toone-fifteenthofrecommendedvolumeswith1ngoftargetDNAinput,andthefragmentation/endstep was optimized to the minimal 5 min incubation at 37°C to avoid DNA over-fragmentation of old samples. Libraries were pooled in equimolar concentration and paired-end sequenced using the Illumina HiSeq X or Novaseq platforms at a read length of 150 bp. In addition to next-generation sequencing and to ascertain some species identities, some samples were selected for barcode sequencing of the COII mitochondrial gene. COII sequences were obtained as described by Roy et al.(2006).Briefly,DNAwasextractedusing Wilson buffer followed by a salting-out procedure, and COIIwasPCRamplifiedusingthemodified A-tLeu and reverse B-tLys primers (Miura et al. 2000). Sequence data were obtained using an automatic DNA sequencer (Applied Biosystems, ABI PRISM 310) and analysed with Sequencing Data software (Applied Biosystems). Phylogenetic analyses For the whole genome sequences, adapters and low-quality bases were trimmed from raw reads using fastp v0.20.1 (Chen et al. 2018). Trimmed reads were assembled using metaSPAdes v3.13 (Nurk et al. 2017).MitochondrialgenomescaffoldswereidentifiedinmetaSPAdesassembliesandannotated using MitoFinder ver. 1.4 (Allio et al. 2020). The newly-generated mitogenomes of 98 samples of Isognathotermes, one Cubitermes, two Nitiditermes and three Ternicubitermes were deposited in GenBank (for accessions and size completeness: see Supp.file3 and ‘Material examined’ of each chapter). We reconstructed the maximum-likelihood phylogeny of species of Isognathotermes using the aboveproduced 104 mitogenomes, supplemented by 60 previously published mitogenomes encompassing most of the known diversity of termites (Cameron et al. 2012; Bourguignon et al. 2015, 2016, 2017; Wu et al. 2018; Wang et al. 2019, 2022, 2023; Hellemans et al. 2022a, 2022b; Arora et al. 2023; Romero Arias et al. 2024). The 37 mitochondrial genes – i.e., 13 protein-coding, two rRNA, and 22 tRNA genes – were aligned using MAFFT ver. 7.305 (Katoh & Standley 2013). Protein-coding nucleotide sequences were translated European Journal of Taxonomy 1024: 1–197 (2025) 16 Fig. 6. Enteric valves of I. fungifaber (Sjöstedt, 1896). A. Worker (DJ 0271). B. Soldier (DJ 0271). C. Imago (DJ 0466), enteric valves of I.finitimus (Schmitz, 1916). D. Worker (DJ 0286). E. Soldier (DJ 0286). F. Imago (DJ 0072). G. Worker enteric valve of a sample of I. severus (Silvestri, 1914) with anintermediatepattern(DJ0659).Allfigurestothesamescale. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 17 The species was later reverted to the genus Cubitermes by Snyder (1949: 161). The genus Isognathotermes was recently restored as valid by Hellemans et al. (2021: 233) based on a phylogenetic analysis. It now gathers several previous Cubitermes species sharing the same kinds of Enteric Valve Architectures (EVAs), i.e., of the fungifaber or finitimuspatternsasdefinedbyJosens&Deligne(2019). Among the genera derived from Cubitermes (sensu Wasmann), Isognathotermes is probably the most confusingwiththemostnumeroussynonymiesandmisidentificationsinmuseumcollections. The mitogenomes of 12 out of the 15 valid species have been sequenced. Species included The genus Isognathotermes clusters 22 taxa previously housed in the genus Cubitermes (sensu Wasmann), namely C. antennalis Sjöstedt, 1924; C. banksi (Emerson, 1928); C. bulbifrons Sjöstedt, 1924; C. comstocki (Emerson, 1928); C.finitimus Schmitz, 1916; C. fungifaber (Sjöstedt, 1896); C. fungifaber var. elongata Sjöstedt, 1924; C. gaigei (Emerson, 1928); C. gibbifrons Sjöstedt, 1924; C. heghi Sjöstedt, 1924; C. kemneri (Emerson, 1928); C. loubetsiensis Sjöstedt, 1924; C. minitabundus (Sjöstedt, 1913); C. modestior Silvestri, 1914; C. planifrons Sjöstedt, 1924; C. schmidti (Emerson, 1928); Fig. 7. Worker’s foreleg of I. ugandensis (Fuller, 1923) (DJ 0669). Note the characteristic strong spines on trochanter and coxa (the spines are inserted on a carina). European Journal of Taxonomy 1024: 1–197 (2025) 18 C. severus Silvestri, 1914; C. silvestrii Sjöstedt, 1925; C. speciosus Sjöstedt, 1924; C. subarquatus Sjöstedt, 1926; C. ugandensis Fuller, 1923; and C. zenkeri (Desneux, 1904). However, 13 of these 22 species are now considered to be junior synonyms of other species, as explained below. In addition, one species previously housed in the genus Cubitermes (sensu Wasmann), namely C. congoensis(Emerson1928)andthreepossiblynewspeciescouldnotbeclassifiedforsure;theyare housed in the Incertae sedis chapter. The genus Isognathotermes also includes seven new species: I. acristatus sp. nov., I. magniplanifrons sp. nov., I. modicus sp. nov., I. phallicaecalis sp. nov., I. phalloides sp. nov., I. rectimalatus sp. nov., and I.similifinitimus sp. nov. Redescription of the genus Imago Colour. Head capsule well sclerotised, dark, C6–C8, paler (up to C4) in long preserved samples. Fontanelle concolorous or almost so with head capsule. Postclypeus C5–C7 concolorous or somewhat paler (up to two levels) than head capsule. Antennae C4–C6 without any difference between proximal and distal articles. Thorax: pronotum C5–C7, somewhat paler than head capsule; mesoand metanotum C5–C7, as pronotum. Legs C3–C5, tibia usually slightly (one level) darker than femur. Wings hyaline with brown to grey tinge (Cf2–Cf4), anterior veins darker. Abdomen: tergites C5–C7, as pronotum. Sternites appreciably paler in middle (C3–C5) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. Setation. Head capsule with some prominent setae, mainly near the eyes, overhanging a generally dense mat of short bristles. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally onmostarticles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: pronotum with prominent setae mainly on margins and many shorter ones in middle; mesoand metanotumwithsomefine,palesetaearrangedinamedio-longitudinalstrip,mainlyonmesonotumand theanteriorlobeofmetanotum,generallyvisibleat20–80×,butsometimeswithoutanyvisiblesmall setae; frequently 1–4 larger setae on metanotum. Legsverypilose,furnished(amongnumerousfine setae) with some large setae becoming sometimes spine-like: 0–18 on the carina of fore coxa and 0–8 on the anterior side of fore coxa; tibia pilose and furnished with 15–30 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 1; Figs 8–12, 23). Size: the imagines of the genus Isognathotermes (with those of the genus Polyspathotermes) are among the largest of those derived from the former genus Cubitermes (sensu Wasmann); however, with large overlapping with Ternicubitermes and Nitiditermes. Thiscanbeseeninmostrawdata,exemplifiedbytheheadwidth(Fig.23);incontrast,indicesdiffer little between genera. Head capsule large; fontanelle generally a tiny round or elongate marking (Fig. 8). Compound eyes round to shortly oval (IEyD/IEyd = 1.00–1.25, Fig. 9). Ocelli round to oval (IOcD/IOcd = 1.00–1.80). Antennae: 16 articles on alate individuals (one out of 278 alate imagines with 17 articles), always shortened by amputation of 1–4 articles in queens and kings. Labrum: cupola shaped, generally wider than long. Left mandible with apical tooth longer and more prominent than firstmarginal;marginalteeththreeinnumberbutsecondoneonlysuggestedbyanundulationofedge betweenfirstandthirdmarginalteeth(disappearinginwornmandibles);onlytheapicaltoothisacutein unworn specimens; premolar tooth with proximal end obscured or partly obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 19 tiny acute apophysis. Right mandiblewithapicaltoothlongerandmoreprominentthanfirstmarginal; marginalteethtwoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhenfresh;second marginal tooth smaller and with a blunt tip even when fresh; molar tooth bearing a ventral rounded flangeandendingposteriorlyinakindofheel(Fig.10).Thorax: pronotum appreciably wider than long (Fig. 11) and narrower than head width, straight to very weakly sellate with anterior lobe short and very slightly elevated. Legs:theforecoxaisflangedventrallyresultinginamoreorlesssharpedgecalled here ‘carina’. Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 2–6 and 7–15 branches respectively (Fig. 12). Abdomen of imagines shows10fullyvisibleundividedtergitesinbothsexes.Thefirststerniteisabsentorvestigial;fully visible undivided sternites are 8 in male and 6 in female. In the male, the 8 visible undivided sternites are followed by a reduced one divided into two paraprocts; in female the sixth visible sternite (genital plate) Table 1. Genus Isognathotermes:rangesofsignificantmeasuresinthethreecastes,inalphabeticalorders of “Code” column. Variable *Code *fungifaber EVA finitimus EVA Imagines (n = 283) Raw measures (mm) Eye: large diameter IEyD0.34–0.58 0.33–0.48 Head: width across the eyes IHdW 1.40–1.84 1.38–1.78 Left mandible: A-m1 distance IMlAmD 0.16–0.28 0.17–0.30 Ocellus: large diameter IOcD0.12–0.23 0.12–0.21 Postclypeus: width IPcW 0.65–0.93 0.65–0.87 Pronotum: maximal width IPnW 1.17–1.74 1.18–1.72 Hind tibia: length IT3L 1.45–2.35 1.30–2.29 Wing: length (n = 127) IWgL 10.4–19.5 12.2–16.8 Index Left apico-marginal index IMlAmD/IMlmmD 0.93–2.06 1.05–2.04 Soldiers (n = 737) Raw measures (mm) Head: upper sagitta SHdC 0.00–0.11 0.00–0.12 Head: length SHdL 2.37–3.72 2.18–3.77 Head: width SHdW 1.58–2.39 1.73–2.49 Left mandible: lesser sagitta SMlc 0.08–0.33 0.13–0.36 Left mandible: ventral length SMlL 1.74–2.99 1.55–2.99 Hind tibia: length ST3L 1.26–1.94 1.40–2.01 Indices Head elongation index SHdL/SHdW 1.22–1.62 1.25–1.67 Left mandible: apical curvature index SMlc/SMlL 0.03–0.15 0.05–0.15 Mandibles: curvature symmetry SMlc/SMrc 0.51–1.24 0.70–1.38 Workers (n = 408) Raw measures (mm) Head: width WHdW 0.94–1.42 1.06–1.43 Left mandible: A-m1 distance WMlAmD 0.13–0.25 0.15–0.22 Left mandible: total length WMlL 0.47–0.69 0.49–0.68 Hind tibia: length WT3L 1.05–1.49 1.12–1.57 Valve: PC average length WVP-AvL 0.43–0.85 0.45–0.77 Valve: PC average width WVP-AvW 0.04–0.12 0.05–0.10 Valve: SC average length WVS-AvL 0.40–0.73 0.36–0.64 Valve: SC average width WVS-AvW 0.19–0.50 0.16–0.41 Index Valve: odd PC elongation index WVPOdd-Elg 5.57–13.6 4.85–11.6 *Abbreviations:seedefinitionsinMaterialandmethods. European Journal of Taxonomy 1024: 1–197 (2025) 20 Fig. 8. Dorsal view of an imago’s head (antennae removed) of I. minitabundus (Sjöstedt, 1913) (DJ 0728). The fontanelle is, in this case, somewhat darker than head capsule. Fig. 9. Lateral view of an imago’s head (antennae removed) of I. minitabundus (Sjöstedt, 1913) (DJ 0728). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 21 is elongated and often covers the three following ones which are divided and reduced, the third having become the two paraprocts. In both male and female each paraproct bears a two-jointed small cercus. Gut:Thegutoftheimagoissimilartothatofworkerswithnotablyawell-definedmixedsegmentand a caecum (Fig. 3), but the caecum is proportionally less developed. Soldier C olour . Head capsule generally Cd4–Cd6 becoming fader and darker (e.g., Cf5–Cf7) in long preserved samples; frons frequently 1–2 levels darker than back (e.g., C6–C7) sometimes with a sharp contrast givingtheimpressionofabicolourhead;thistwo-tonecolouringhasnospecificvalue.Gulamentum concolorous with head or somewhat darker. Antennae and labrum one level paler than head capsule. Mandibles dark (C7–C8) generally with an abrupt clearing on their bases (two levels) which are generally of the same colour as frons. Thorax, nota and legs paler than head capsule (C3–C5) somewhat darker in long preserved samples. Abdomen grey to red-brown owing to digestive bolus, sometimes with a yellow tinge on tergites. Setation. Head capsulewithfewscatteredfinesetae;onfronsadensebunchofsetaesurroundsand overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Labrum always with 4–9 large setae on each lobe. Thorax: proand mesonotum with some setae mainly located on fore and hind margins. Legs: fore coxa furnished with 0–3 spines on carina and not any (or rarely one) spine on ventral side; trochanter generally with six or seven long lined-up strong setae or spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively; all tibiae furnished with a row of 6–15 spines. Abdomen: tergites with few large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. Fig. 10. Mandibles of an imago of I. minitabundus (Sjöstedt, 1913) (DJ 0728). European Journal of Taxonomy 1024: 1–197 (2025) 22 StruCture (measurements in Table 1; Figs 13–17, 24). Size: the soldiers of Isognathotermes (with those of Polyspathotermes) are among the largest of those derived from the former genus Cubitermes (sensu Wasmann); however, with some overlapping with Ternicubitermes and Nitiditermes. This can be seeninmostrawdatathatvarywithgenus,exemplifiedbytheheadlength(Fig.24);incontrast,most indices differ little between genera. Head capsule always clearly sclerotised and appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a more or less strong narrowing near posterior third or fourth (Fig. 13); however, in the soldiers of incipient colonies, lateral sides are slightly convex without any narrowing; posterior side variable: regularly rounded or sometimes with a short straight or even concave part in the middle, or with three short straight or even concave parts. In profile: upper profilealwaysmoreorlessconcave,alsointhecaseofsoldiersfromincipientcolonies;anglebetween extended mandibles and frons varies from almost right to 130°; frons with or without any small frontal hump overhanging the fontanelle (Fig. 14). Gulamentum:profilegenerallywithaflatposteriorpart;in ventral view always more or less constricted in its posterior half, with sides of anterior part variable, from smoothly rounded (Fig. 15) to extended into a kind of angular ears. Antennae generally of 15 articles Fig. 11. Dorsal view of an imago pronotum of I. minitabundus (Sjöstedt, 1913) (DJ 0728). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 23 (14.5 articles in 9%, 14 articles in 6% and only 13 articles in one soldier from an incipient colony). Labrum: always deeply bifurcate and generally wider than long, generally (in 82%) with sinuous sides (lyre-shaped labrum) (with convex sides in 11%, or with straight sides in 7%) and almost always withsubtruncatedlobesendinginfine,whitishortranslucenttips;anteriormarginconcave(Fig.16). Mandibles: sabre-like to almost hooked distally; inner edges smooth with one distinct but generally very small marginal tooth near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible generally slightly more curved than left. Thorax: pronotum sellate, narrower than head width, with generally entire anterior and posterior margins (Fig. 17). Fore coxaflangedventrallyresultinginamoreorlesssharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions generally showing trilateral symmetry: the odd primary cushions are on average 16% longer Fig. 12. Left anterior wing of an imago of I. minitabundus (Sjöstedt, 1913) (DJ 0728). Fig. 13. Dorsal view of a soldier’s head (antennae and labrum removed) of I.finitimus (Schmitz, 1916) (DJ 0739). Note a slight narrowing near posterior fourth of the head capsule. In this case, the head capsule seems to be bicolorous. European Journal of Taxonomy 1024: 1–197 (2025) 24 than the even cushions; the odd cushions generally without any crest or with crests weakly developed; in the species with finitimus EVAs the pilosity becomes abruptly very dense showing the place where a crest would be expected (in comparison with the worker’s EVA); secondary cushions wide at the upstream end narrowing noticeably downstream with a homogeneous spine scattering. Caecum rather small, visible in Fig. 14. Lateral view of a soldier’s head (antennae and labrum removed) of I.finitimus (Schmitz, 1916) (DJ0739).Note,inthiscase,aweakdorsalbulge(=upperprofileweaklyconcave)andnotanyforward frontal hump. Fig. 15. Ventral view of a soldier’s head of I.finitimus (Schmitz, 1916) (DJ 0739). In this case, the sides of anterior part of gulamentum are smoothly rounded. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 25 ventralview,nearcentreofabdomen,eithershortlylobed(inmostspecies)ordevelopedasafinger-like process that is sometimes capped or swollen distally. Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always 1–2 levels darker (C4–C5). Thorax, nota and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust, scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with scattered setae. Legs:forecoxaalwayscarinated,bearingonefinesetaandfurnished with 3–7 spines on carina (only 2 spines in two out of 400 samples) and 0–4 spines on ventral side; fore trochanter with 5–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs, and 0, 2, 0 subapical spurs respectively and a row of spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. Fig. 16. Labrum of a soldier of I.finitimus (Schmitz, 1916) (DJ 0739). Note the characteristic lyre shape and the subtruncated lobes, ending in whitish, almost translucent tips. European Journal of Taxonomy 1024: 1–197 (2025) 32 Fig. 28. Comparison of soldiers’ head lengths (in µm) in the genus Isognathotermes Sjöstedt, 1926. Red circles = species with a fungifaber EVA; green triangles = species with a finitimus EVA and a phalloid caecum; blue diamond shapes = species with a finitimus EVA and a small lobed caecum. 1 = I. acristatus sp. nov.; 2 = I. fungifaber; 3 = I. minitabundus; 4 = I. severus; 5 = I. ugandensis; 6 = I. zenkeri; 7 = I. phallicaecalis sp. nov.; 8 = I. phalloides sp. nov.; 9 = I. bulbifrons; 10 = I.finitimus; 11 = I. magniplanifrons sp. nov.; 12 = I. modicus sp. nov.; 13 = I. planifrons; 14= I. rectimalatus sp. nov.; 15 = I.similifinitimussp. nov.; empty red circles = I. modestior (regarded as synonymous with I. severus); empty blue diamond shapes = incipient or young colonies of I. bulbifrons+I. congoensis (considered a possible synonym of I. bulbifrons). Fig. 29. Comparison of soldiers’ left mandible apical curvature indices in the genus Isognathotermes Sjöstedt, 1926; same symbols and same abscissa as in Fig. 28 but I. modestior (regarded as synonymous with I. severus) mixed with other I. severus and very young colonies of I. bulbifrons+I. congoensis (considered a possible synonym of I. bulbifrons) mixed with other I. bulbifrons. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 33 Fig. 30. Comparison of workers’ head widths (in µm) in the genus Isognathotermes Sjöstedt, 1926. Red circles = species with a fungifaber EVA; green triangles = species with a finitimus EVA and a phalloid caecum; blue diamond shapes = species with a finitimus EVA and a small lobed caecum. 1 = I. acristatus sp. nov.; 2 = I. fungifaber; 3 = I. minitabundus; 4 = I. severus; 5 = I. ugandensis; 6 = I. zenkeri; 7 = I. phallicaecalis sp. nov.; 8 = I. phalloides sp. nov.; 9 = I. bulbifrons; 10 = I.finitimus; 11 = I. magniplanifrons sp. nov.; 12 = I. modicus sp. nov.; 13 = I. planifrons; 14= I. rectimalatus sp. nov.; 15 = I.similifinitimussp. nov.; empty red circles = I. modestior (regarded as synonymous with I. severus); empty blue diamond shapes = incipient or young colonies of I. bulbifrons+I. congoensis (considered a possible synonym of I. bulbifrons). Fig. 31. Comparison of workers’ average lengths (in µm) of the enteric valve primary cushions (PCs) in the genus Isognathotermes Sjöstedt, 1926; same symbols and same abscissa as in Fig. 30. European Journal of Taxonomy 1024: 1–197 (2025) 34 Ideally,therefore,allthreecastesshouldbeavailableforproperidentification,bearinginmindthat Isognathotermes termite mounds, especially older ones, often contain several species and can lead to misidentification. An initial distinction between finitimus–type and fungifaber–type EVAs is essential: a Principal Component Analysis (PCA) on the soldiers’ morphology involving all the species seems indeed confusing (Fig. 20). However, applying a PCA separately to species with a fungifaber–type EVA (Fig. 21) and those with a finitimus–type EVA (Fig. 22) results in better (though not yet complete) separation of the species. Nevertheless, it is important to note that creating sub–genera based on EVA types is not feasible because they do not delineate two distinct clades. Colour does not provide any diagnostic criterion: it depends on both the age of the individual at the time of capture and the time spent in the alcohol before being studied. Chorology-ecology This genus has been collected in forests and savannahs of West, Central, and East Africa, from Gambia to Kenya and from Angola to Malawi (Fig. 32). The species with a finitimus EVA are almost restricted to forested areas of central Africa while the species with a fungifaber EVA or an intermediate EVA can be found in forests and savannahs and is therefore present in a much larger area, from west to east equatorial Africa. There are only a few localities where species with finitimus and fungifaber EVAs coexist (Fig. 32). All species are soil feeders. Fig. 32. Distribution map of the genus Isognathotermes Sjöstedt, 1926: species with a fungifaber or an intermediate EVA (red dots), species with a finitimus EVA (blue triangles). Note that very few localities host species from both groups together. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 35 Fig. 33. Phylogenetic relationships between species of Isognathotermes Sjöstedt, 1926. The tree was reconstructed with IQ-TREE from complete mitogenomes with 41 partitions (see methods). Node support values are Shimodaira-Hasegawa approximate likelihood-ratio/Ultrafast bootstrap (SH-aLRT/UFB). Intra-specificsupportvaluesonshortedgeswereomittedforclarity.Numbersaftertheslashinthestudy code indicate the type of enteric valve (Josens & Deligne 2019): /11 = bilobatus pattern; /12 = muneris pattern; /13 = oculatus pattern; /14 = bilobatodes pattern; /15 = fungifaber pattern; /16 = finitimus pattern; /22 = sankurensis pattern; /23 = oblectatus pattern; /26 = sulcifrons pattern. The mention “type” in the label indicates specimens sequenced from the type series. Red edges and labels indicate the intricate paraphylies of I.similifinitimussp. nov. and I. phallicaecalis sp. nov. The complete reconstruction is presented in Supp.file1. European Journal of Taxonomy 1024: 1–197 (2025) 36 Phylogenetic analyses Our phylogenetic tree integrates the mitogenomes of 101 samples from the genus Isognathotermes (Fig. 33). Mitogenome similarities between all members of Isognathotermes are larger than 91.23% (Table ST2). These analyses revealed that the analysed samples belonged to 12 lineages (out of the 15morphologicalvalidspeciesreportedherein),excludingtheunidentifiedspeciesrepresentedby the samples DJ P141 and DJ 0937. All species were monophyletic, with the exception of the intricate paraphylies of I.similifinitimus sp. nov. and I. phallicaecalis sp. nov. Note that our exclusive use of (maternally-inherited) mitogenomes may have limited our ability to fully resolve the evolutionary relationships among species of Isognathotermes. The12speciescouldfurtherbesubdividedintofivemainclades.Thefirstfourcladesaremonospecific, all supported by SHalrt > 99 and UFB = 100, and respectively composed of: the species (i) I. acristatus sp. nov.; (ii) I. rectimalatus sp. nov.; (iii) I. bulbifrons; and (iv) I. fungifaber.Thefifthcladecombinesthe eight remaining species: I. severus, I. minitabundus, I. ugandensis,I.finitimus, I. phallicaecalis sp. nov., I. phalloides sp. nov., I. planifrons, andI.similifinitimus sp. nov., While the relationships among species ofthefirstfourcladesarehighlysupported(SHalrt>99andUFB=100),therelationshipsbetween speciesofthefifthcladeareunresolved. Interestingly, the clades evidenced from the mitogenomic tree did not perfectly match EVA patterns. While clades I and IV are limited to the fungifaber EVA, and clades II and III to the finitimus EVA; the last unresolved clade V groups species exhibiting both EVAs. Additionally, we reconstructed a phylogenetic tree based on the COII gene (Supp.file2) to study the placements of samples from Roy et al. (2006) and Hellemans et al. (2021) in the herein presented larger sampling of Isognathotermes. The COII tree included 120 samples of Isognathotermes, and recovered similar patterns as the mitogenome-based tree including the paraphyly of I.similifinitimus sp. nov. and I. phallicaecalis sp. nov. In addition, both I. phalloides (DJ 0459) and I. aff. planifrons (DJ P141) were inserted within I. severus.WespecificallydetailourreanalysesofsampleswithinI. fungifaber and I. planifrons in their respective sections. Identification key Isognathotermesspeciesshowveryhighintraspecificvariability:Figs26–31clearlyshowtheextentto whichthemeasurementsofdifferentspeciesoverlap.Intheabsenceofmoleculardata,theidentification of Isognathotermesspeciesthusremainsdifficultanditwasnotpossibletoproduceanaccuratekeybased on a single caste. We also remind the reader that several species may live together in the same termite mound,therebycomplexifyingtheidentificationtask.Asfewselectedmeasuresarerarelysufficient to recognise a species, a multidimensional approach (PCA) has been used in this study; however, such multidimensional approach cannot be easily incorporated into a dichotomous key. The dissection of a worker is essential to recognise its enteric valve and caecum types; precise measurements of soldiers’ head and mandible length and curvature (in ventral view) are required as well as geographic origin. TheidentificationkeybeginswiththegeneraderivedfromCubitermes sensu Wasmann (items 1–4) and then gives the species of Isognathotermes (items 5–18). Incipient colonies (one or two soldiers with some workers and a non-physogastric queen) are excluded from the key. Abbreviations: see the chapter Material and methods. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 37 1. Workerandsoldier:conicalforecoxaebearingsomefine,softsetaebutnotanyspinesorspine-like setae. Imagines: conical fore coxae bearing many soft setae ............................................................ 2 – Worker and soldier: carinated fore coxae bearing some spines or spine-like setae (rarely none in the soldier). Imagines: carinated fore coxae bearing some spine-like setae among many other soft setae ........................................................................................................................................................... 3 2. PCs of the workers valve bearing no more than 3–6 supporting bristles on each side; SCs generally with a heterogeneous scattering of spines (the spines are lacking in some irregular spots). This criterion also applies, albeit less clearly, to soldiers ............................................................................ ............................................................... Cubitermes Wasmann, 1906 (sensu Hellemans et al. 2021) – PCs of the worker’s valve bearing 10–30 supporting bristles on each side; SCs with either a homogeneous scattering of the spines, or with a heterogeneous scattering tending towards the shape of a spearhead .....................................................................Ternicubitermes Josens & Deligne, 2021 3. Worker and soldier EVAs: SCs narrow (not wider or only slightly wider than the PCs). Generally, twoPCsendinginasclerifiedspatulabut,insomesamplesfromWestAfrica,notanyspatulaand, in this case, PC1 much longer than the others (WVP1-bil = 1.42–1.62). Soldiers on average smaller: SHdL = 1.55–2.45 mm ...........................................................................Nitiditermes Emerson, 1960 – Worker and soldier: SCs clearly wider than the PCs; PC1 equal to or somewhat longer than the others (WVP1-bil = 1.00–1.26). Soldiers on average larger: SHdL = 2.05–3.80 mm ................................. 4 4. Soldier:triangularorfinger-shapedlabrumlobes.WorkerandsoldierEVAs:threetosixPCsbearing asclerifiedspatula(onlysketchedinsomesoldiers) .......Polyspathotermes Josens & Deligne, 2021 – Soldier: lyre-shaped labrum or with triangular lobes. Worker and soldier EVAs: PCs not spatulated (orsometimeswithsoft,notsclerifiedspatulas) ...........................5 Isognathotermes Sjöstedt, 1926 5. Worker’s EVA: odd PCs distally narrowed and crested and bearing strong, long bristles: fungifaber EVA, Figs 4, 6, sometimes an intermediate EVA, Fig. 6) but one species, I. acristatus sp. nov., with a bilobatodes EVA) ............................................................................................................................ 6 – Worker’s EVA: odd PCs distally barely narrowed, rather swollen and bearing numerous strong, short setae: finitimus EVA (Figs 5–6) ........................................................................................................11 6. Sample from regions south or east of the Congolian forests; soldier’s left mandible on average less curved (SMlc = 0.08–0.24 mm); asymmetrical curvature of the mandibles: the right is generally more curved than the left (SMlc/SMrc = 0.51–1.03) .................................................................................. 7 – Sample from West Africa or regions north of the Congolian forests; soldier’s left mandible on average more curved (SMlc = 0.14–0.33 mm); curvature of the mandibles less asymmetrical, SMlc/SMrc = 0.79–1.24) .......................................................................................................................................... 9 7. Smaller soldier (SHdL = 2.44–2.59 mm); worker’s valve with almost non-existent crests on the odd PCs (bilobatodes EVA); sample from Angola ....................... I. acristatus Josens & Deligne sp. nov. – Larger soldier (SHdL = 2.91–3.72 mm); worker’s valve with well-developed crests on the odd PCs; sample from a more eastern country .................................................................................................. 8 8. Twospeciesverydifficulttodistinguishwithoutsequencing.SamplefromEastAfrica(from Uganda to Northern Zambia: Fig. 49).Foursubspecies,onlyidentifiablefromimagines,seechapter I. ugandensis ...........................................................................................I. ugandensis (Fuller, 1923) – Sample from the DRC (Kasaï–Katanga) or Northern Zambia (Fig. 49) .............................................. ......................................................................................................... I. minitabundus (Sjöstedt,1913) European Journal of Taxonomy 1024: 1–197 (2025) 38 9. Soldier with longer mandibles (SMlL = 2.75–2.99 mm in ventral view); sample from Cameroon ................................................................................................. I. zenkeri (Desneux, 1904) – Soldier with shorter mandibles (SMlL = 1.74–2.58 mm) ............................................................... 10 10.Twospeciessometimesdifficulttodistinguishwithoutsequencing.Onaverage,smallersoldier (SHdL = 2.37–3.11 mm, ST3L = 1.26–1.67 mm), smaller worker (WHdW = 0.94–1.25 mm), imago of the same size; sample of evergreen forests from southern RCI to Gabon (Fig. 45) ....................... ...............................................................................................................I. fungifaber (Sjöstedt,1896) – On average, larger soldier (SHdL = 2.43–3.29 mm, ST3L = 1.52–1.93 mm), larger worker (WHdW = 1.06–1.26 mm), imago of the same size; sample from various ecosystems (savannah, orchard, woodland, forest gallery or secondary forest, or from the evergreen forest in RCI near the border with Liberia or from the Lobaye province, CAR); large geographical range across Africa from Gambia to CAR (Figs 45, 49) ......................................................................................I. severus (Silvestri, 1914) 11.Soldier’sandworker’scaecumextendedforwardinafinger-likeprocess,sometimesswollen,or capped distally (phalloid caecum, Figs 55–56) ............................................................................... 12 – Soldier’s and worker’s caecum rather small, generally with 2–5 short lobes (Fig. 2) sometimes a small amorphous button ................................................................................................................... 13 12. Mandibles, on average, less curved SMlc = 0.18–0.26 mm, sample from the evergreen Congolian forest (Congo Republic, Cameroon) ...............................I. phallicaecalis Josens & Deligne sp. nov. – Mandibles, on average, more curved SMlc = 0.19–0.33 mm, sample from gallery forests in the southwest and west of the DRC of from northern Angola ............ I. phalloides Josens & Deligne sp. nov. 13. Smaller species (SHdL = 2.42–2.66 mm) from Gabon ...........I. modicus Josens & Deligne sp. nov. – Larger species (SHdL = 2.65–3.77 mm) ......................................................................................... 14 14. Worker’s left mandible with a larger apico-marginal distance (WMlAmD = 0.20–0.21 mm), soldier’s mandibles, especially the right one, very slightly curved (SMrc = 0.13–0.19 mm, SMrC = 0.20– 0.25 mm); sample from Angola ........................................ I. rectimalatus Josens & Deligne sp. nov. – Worker’s left mandible generally with a smaller apico-marginal distance (WMlAmD = 0.15– 0.22 mm); soldier’s mandibles generally more curved (SMrc = 0.16–0.38 mm, SMrC = 0.24– 0.49 mm); sample from elsewhere .................................................................................................. 15 15. Larger species (SHdL = 2.98–3.77 mm) from Haut-Uele or Kivu, DRC ............................................ ....................................................................................I. magniplanifrons Josens & Deligne sp. nov. – Generally smaller species (SHdL = 2.60–3.76 mm) from elsewhere ............................................. 16 16. Soldier’s head generally more heavily humped (SHdC = 0.01–0.12 mm); worker’s valve with longer secondary cushions (WVS-AvL = 0.47–0.62 mm) .............................. .I. bulbifrons (Sjöstedt,1924) – Soldier’s head generally more slightly humped (SHdC = 0.01–0.08 mm); worker’s valve with shorter secondary cushions (WVS-AvL = 0.38–0.56 mm) ......................................................................... 17 17. Soldier’s mandibles somewhat more curved (SMlc = 0.19–0.35 mm); indistinguishable workers and imagines; sample from forests of western-central Africa (Cameroon, CAR, Gabon, Congo and Kongo-Central, DRC, Fig. 47) ............................................................ .I. planifrons (Sjöstedt,1924) – Soldier’s mandibles somewhat less curved (SMlc = 0.16–0.31 mm); indistinguishable workers and imagines; sample from continental forests of central Africa .......................................................... 18 JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 39 18. Two species indistinguishable without sequencing; sample from the continental forests of Central Africa (CAR, DRC, Uganda, Fig. 38) ................................................... I. finitimus (Schmitz, 1915) – Cryptic species; only one site known to date, south of Kisangani, DRC (Fig. 47) .............................. ........................................................................................I. similifinitimus Josens & Deligne sp. nov. Valid species and subspecies Isognathotermes acristatus Josens & Deligne sp. nov. urn:lsid:zoobank.org:act:D984D1ED-5165-427D-9F6F-3AA7D263967C Figs 26–34, distribution map: Fig. 47; Table 2 Diagnosis This species is rather atypical in the genus Isognathotermes; the worker is small sized and characterised by its odd PCs without crests but furnished with strong setae at the place where crests would be expected (Fig. 34); it could therefore be confused with a species of Ternicubitermes (bilobatodes EVA). The PCs carry a low number (5–10) of supporting bristles; it could therefore also be confused with a species of Cubitermes (sensu Hellemans et al. 2021). However, it has carinated fore coxae bearing 3–4 strong spines (the workers of Ternicubitermes and Cubitermes have unarmed conical coxae). It is also characterised by a high PC elongation index: WVPOdd-Elg = 9.79–13.6. The soldier is small sized in the genus Isognathotermes and can be recognised by its very weakly curved mandibles (even less curved than those of I. rectimalatus sp. nov.): SMlc = 0.11–0.16 mm. The imago is medium sized in the genus Isognathotermes and can hardly be distinguished from I. severus or I. ugandensis ugandensis. It has larger ocelli than I. ugandensis (IOcD = 0.20–0.22 mm). To date, this species is only known from Angola. Etymology The epithet acristatus, fromGreekα(without)andLatincristatus (crested) refers to the quasi absence of crests on the odd PCs of the enteric valve, even in the worker caste. Material examined Four samples from two locations. Holotype ANGOLA•soldier;Mussende;10°33.17′S,15°39.492′E;25Oct.2021;M.Hassonleg.;studycode: DJ 0811; GenBank no PQ679177 (mitogenome); BE RMCA INS.Iso.059148. Paratypes ANGOLA•soldier,worker,♂(alate),♀(queen);samedataasforholotype;BERMCAINS.Iso.059149. Other material examined ANGOLA•soldier,worker;CangandalaN.P.;9°49.33′S,16°40′E;1Mar.2019;M.Viageleg.;study code: DJ 0865; GenBank no PQ679228 (mitogenome); BE RMCA INS.Iso.059145 • soldier, worker; CangandalaN.P.;9°49.33′S,16°40′E;1Mar.2019;M.Viageleg.;studycode:DJ0866;GenBankno PQ679192 (mitogenome); BE RMCA INS.Iso.059147 •soldier,worker;CangandalaN.P.;9°49.33′S, 16°40′E;1Mar.2019;M.Viageleg.;studycode:DJ0868;BERMCAINS.Iso.059146. European Journal of Taxonomy 1024: 1–197 (2025) 40 Historical review Specimens of this species were recently collected by two of us (MV & MiH) in Angola; the imago, the soldier, and the worker are described here. Description Imago C olour . Head capsule: well sclerotised and dark (C6); fontanelle slightly (one level) paler. Postclypeus concolorous with head capsule. Antennae C4–C5. Thorax: pronotum concolorous with head capsule; mesoand metanotum C4 slightly paler than head. Legs tibia C5 slightly paler than femur C4. Abdomen: tergites C5. Sternites appreciably paler in middle (C3) with both sides darker (C5) posterior sternites darker (C4–C5) than anterior. Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,visibleat80×,withsomelargesetae on posterior lobe. Legsverypilose,furnished(amongnumerousfinesetae)with9–10strongersetaeon the carina of fore coxa and 3–4 on the ventral side of fore coxa and 8–9 on trochanter; tibia pilose, fore, mid, and hind tibia furnished with 15–30 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 2, Fig. 34). Size: the imagines of I. acristatus sp. nov. are medium sized in the genus Isognathotermes (Fig. 26). Head capsule: compound eyes shortly oval; ocelli rather large (IOcD > 0.20 mm) oval, removed from eyes by a distance equal to 0.8–0.9 ocellus small diameter; fontanelle generally a tiny round or elongate marking. Antennae: 16 articles, shortened to 13 by amputation in queen. Labrum: cupola shaped, wider than long. Left mandible with apical tooth smallsizedinthegenus(Fig.27)andmoreprominentthanfirstmarginal;marginalteeththreeinnumber butsecondoneonlysuggestedbyanundulationofedgebetweenfirstandthirdmarginalteeth;only the apical tooth is acute in unworn specimen; premolar tooth unobstructed and clearly visible in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandiblewithapicaltoothalwaysmoreprominentthanfirstmarginal;marginalteeth two in number; second marginal tooth with a blunt tip even when fresh; molar tooth bearing a ventral roundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum appreciably wider than long and narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxaflangedventrallyresultinginasharpcarina.Gut not studied. Soldier Colour. Head capsule C4–C6. Antennae and labrum concolorous or somewhat paler than head capsule. Mandibles dark (C6–C8) with an abrupt clearing on their bases (two levels) which is generally the same colour as frons. Thorax and legs paler than head capsule (C2–C4). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Labrum with 4–5 large setae on each lobe. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs:forecoxawithatleastonefinesetaand2–6spinesorstrongsetaeon JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 41 carina and not any spine on ventral side; trochanter generally with some strong lined-up setae; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 6–15 spines along their shaft. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 2, Fig. 34). Size: the soldiers of I. acristatus sp. nov. is among the small soldiers in the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised; appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a very slight narrowing near posterior third or fourth; from antennal sockets sides converge towards bases of mandibles; posterior side regularly convex. Slightly to strongly concave upper profile; angle between extended mandibles and frons obtuse; frons with a small bump that overhangs the fontanelle. Gulamentum in ventral view constricted in its posterior half, with sides of anterior part smoothly rounded to extended into a kind of angular ears. Antennae: of 14–15 articles. Labrum: deeply bifurcate and wider than long, with almost straight sides; rounded lobes without translucent tips; anterior margin concave. Mandibles: sabre-like; inner edges smooth with one distinct but small marginal tooth, near molar tooth on each Fig. 34. Isognathotermes acristatus Josens & Deligne sp. nov.: imago, soldier, and worker. A. Lateral and dorsal views of an alate male’s head capsule from the I. acristatus type colony (DJ 0811), and dorsal view of this imago’s mandibles. B. Lateral and dorsal views of a soldier’s head capsule from the type colony, ventral view of its mandibles, and dorsal view of its labrum. C. PC1s of soldier’s and worker’s enteric valves from the type colony, caecum and foreleg of this worker. European Journal of Taxonomy 1024: 1–197 (2025) 48 Collins;theyareidentifiedasI. bulbifrons based on their queens (not at all physogastric but wingless andwithshortenedantennae).Ifthesoldiershadbeenusedinstead,theresultingidentificationwould have be ‘I. congoensis’. It is indeed well known (Noirot 1955; Mathot 1964; and personal (G.J., J.D.) observations)thatthefirstsoldiersandworkersproducedbyyoungcoloniesaresignificantlysmaller thanthesoldiersandworkersofmaturecolonies.InthePCA(Fig.22),theellipselabelled“c+b”pools I. congoensis and the young societies of I. bulbifrons: it shows a strong difference of size (x-axis) from mature colonies (labelled ‘bulb’); moreover, it is stretched because it is made up on the one hand of the two incipient colonies plus the two I. congoensis samples (the four points furthest to the left = smallest individuals) and, on the other hand, of the two very young colonies (slightly larger individuals). Therefore,thesamplesidentifiedasI. congoensis (the imagines of them being unknown), might also be incipient colonies of I. bulbifrons, hence their location in the chapter Incertae sedis. Redescription Imago The description provided by Emerson (1928: 511–513) under the name Mirotermes (Cubitermes) heghi concerned in fact Cubitermes (now Polyspathotermes) sulcifrons. The imago of P. heghi has indeed a much smaller fontanelle and, among the species of the former Cubitermes genus of West Africa, only imagines of P. sulcifronsshowafontanelleaslargeasthatdescribedandfiguredbyEmerson(Josens& Deligne 2019: 62). Further, the imago of Cubitermes kemneri was never described, so the imago of I. bulbifrons was only described to-date by Sjöstedt (1926: 247–248) based on alates and queen from Gabon (not examined). Colour. Head capsule: well sclerotised, dark, C6–C7; fontanelle concolorous or almost so with head capsule. Postclypeus C5–C6 slightly paler (one level) than head capsule. Antennae C5–C6 without any difference between proximal and distal articles. Thorax: pronotum C6–C7, as head capsule; mesoand metanotum C6–C7, as pronotum. Legs C4–C5, tibia usually slightly (one level) darker than femur. Wings hyaline with brown to grey tinge (Cf3–Cf4), anterior veins darker. Abdomen: tergites C6–C7. Sternites appreciably paler in middle (C3–C4) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. Setation. Head capsule with some prominent setae, mainly near the eyes, and a higher density of shorter, finersetaeeverywhere.Labrumandpostclypeuswithsomeprominentsetaemixedwithshorterones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyatmagnification50×ormore).Thorax: pronotum with prominent setae mainly on margins and many shorter ones in middle; mesoand metanotum with somefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat20–40×;sometimes three to four larger setae on metanotum. Legsverypilose,furnished(amongnumerousfinesetae)with somefinespines:6–11onthecarinaofforecoxaand1–3ontheventralside;tibiapilose;fore,mid, and hind tibia furnished with 30–40 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 3; Figs 26–27, 35). Size: the imagines of I. bulbifrons are, on average, rather variable (Fig. 26); some individuals (with I. zenkeri), have the largest apical teeth and the largest apico-marginal distances (IMlAmD = 0.20–0.30 mm (Fig. 27). Head capsule: compound eyes nearly round; fontanelle generally a tiny elongate marking; ocelli nearly round to oval removed from eyes by a distance about equal to 0.7 to 1.3 ocellus small diameter. Antennae: 16 articles on alate individuals, always shortened by amputation by one to three articles in queens and kings. Labrum: cupola shaped. Left mandible with apical tooth, on average, longer than in most other species of the genus andalwayslongerandmoreprominentthanfirstmarginal;marginalteeththreeinnumberbutsecond oneonlysuggestedbyaslightundulationofedgebetweenfirstandthirdmarginalteeth;onlytheapical JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 49 tooth is acute in unworn specimens; premolar tooth with proximal end obscured or partly obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible with apical tooth always longer and more prominentthanfirstmarginal;marginalteethtwoinnumber;firstmarginaltoothwelldevelopedwitha sharp tip when fresh; second marginal tooth smaller and with a blunt tip even when fresh; molar tooth bearingaventralroundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum appreciably wider than long and slightly narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxaflangedventrallyresultinginasharp carina. Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 2–3 and 10–11 branches, respectively. Soldier C olour . Head capsule generally Cd4–Cd6 becoming fader and darker (e.g., Cf5–Cf7) in long preserved samples;thereisfrequentlyagradientfromadarkerfronstoapalerback(e.g.,C6→C4).Gulamentum concolorous with or somewhat darker than head. Antennae and labrum somewhat paler (one to two levels) than head capsule. Mandibles dark (C7–C8) generally with an abrupt clearing on their bases (two palette levels) which is generally the same colour as frons. Thorax, nota and legs paler than head capsule Fig. 35. Isognathotermes bulbifrons (Sjöstedt, 1924) and junior synonym species: imagines. Lateral and dorsal views of an imago’s head capsule, and dorsal view of this imago’s mandibles. A. Physogastric queen of a mature colony (DJ 0727). B. Non-physogastric queen of an incipient colony (DJ 0725). C. King from a non-type colony of Cubitermes gibbifrons (DJ 0615). The type samples did not contain any imago. European Journal of Taxonomy 1024: 1–197 (2025) 50 (C3–C5) somewhat darker in long preserved samples. Abdomen grey to red-brown owing to digestive bolus, sometimes with a yellow tinge on tergites. Setation. Head capsule with few scattered setae; on frons a dense bunch of hair-like setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distalextremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50× or more). Labrum always with 5–9 large setae on each lobe. Thorax: proand mesonotum with some setae located mainly on margins. Legs: fore coxa furnished with 0–3 spines on carina and not any one on ventral side; trochanter generally with some long lined-up setae, sometimes with four to seven spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively; all Table 3. Isognathotermes bulbifrons(Sjöstedt,1924):rangesofsignificantmeasuresinthethreecastes, in alphabetical orders of the “Code” column. The four incipient or young colonies are excluded from the measurements. Variable *Code *Range Type Imagines (n = 15) Raw measures (mm) Eye: large diameter IEyD0.33–0.47 NA Head: width across the eyes IHdW 1.44–1.73 NA Left mandible: A-m1 distance IMlAmD 0.20–0.30 NA Ocellus: large diameter IOcD0.14–0.20 NA Postclypeus: width IPcW 0.71–0.87 NA Pronotum: maximal width IPnW 1.30–1.72 NA Hind tibia: length IT3L 1.66–2.04 NA Wing: length (n = 2) IWgL 14.1–16.8 NA Index Left apico-marginal index IMlAmD/IMlmmD 1.25–2.04 NA Soldiers (n = 64) Raw measures (mm) Head: upper sagitta SHdC 0.01–0.12 0.09 Head: length SHdL 2.65–3.76 3.36 Head: width SHdW 1.82–2.45 2.23 Left mandible: lesser sagitta SMlc 0.14–0.31 0.26 Left mandible: ventral length SMlL 2.12–2.87 2.49 Hind tibia: length ST3L 1.51–2.01 1.85 Indices Head elongation index SHdL/SHdW 1.36–1.67 1.50 Left mandible: apical curvature index SMlc/SMlL 0.06–0.11 0.10 Mandibles: curvature symmetry SMlc/SMrc 0.70–1.20 0.95 Workers (n = 40) Raw measures (mm) Head: width WHdW 1.11–1.43 1.34 Left mandible: A-m1 distance WMlAmD 0.16–0.22 0.21 Left mandible: total length WMlL 0.54–0.67 0.63 Hind tibia: length WT3L 1.24–1.55 1.51 Valve: PC average length WVP-AvL 0.56–0.77 0.69 Valve: PC average width WVP-AvW 0.06–0.10 0.09 Valve: SC average length WVS-AvL 0.47–0.62 0.53 Valve: SC average width WVS-AvW 0.21–0.33 0.25 Index Valve: odd PC elongation index WVPOdd-Elg 6.49–10.3 7.27 *Abbreviations:seedefinitionsinMaterialandmethods. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 51 tibiae furnished with a row of 6–15 spines. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 3; Figs 28–29, 36). Size: the soldiers of I. bulbifrons are rather variable, the largest of them are (with those of I. magniplanifrons) the largest of the genus Isognathotermes; this is best seen in the length of the soldiers’ heads (Fig. 28). Head capsule: always clearly sclerotised and appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a narrowing near posterior third or fourth (however, in the soldiers of incipient or very young colonies, lateral sides are slightly convex without any narrowing); from antennal sockets sides converge more or less clearly towards bases of mandibles; posterior side variable. In profile:upperprofilealwaysclearly concave, even in soldiers from incipient colonies; frons with a small frontal hump (rarely with no hump) overhanging the fontanelle, even in soldiers from incipient colonies. Gulamentum in ventral view always more or less constricted in its posterior half, with sides of anterior part softly curved or forming an acutewideningorevenakindofearoneachside;generally,withaflatposteriorpartfromsideview. Antennae: of 15, sometimes 14.5, articles (only 13 articles in one soldier from an incipient colony). Labrum: always deeply bifurcate and wider than long, with sides generally lyre-shaped, rarely straight; lobesangular,withfine,whitishortranslucenttips;anteriormarginconcave.Mandibles: sabre-like, almost hooked distally; inner edges smooth with one distinct but generally very small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible generally slightly more curved than left. Thorax: pronotum sellate, as wide as 52–68% of head width, with generally entire anterior and posterior margins. Fore coxaflanged ventrally resulting in a carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions showing trilateral symmetry: the odd cushions are on average 17% longer than the even cushions, generally without any hump or with humps weakly developed, however, the pilosity becoming abruptly very dense shows the place where a hump is expected (Fig. 6); secondary cushions wide at the upstream end narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, best seen in ventral view, near centre of abdomen, lobed (two or three small lobes). Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always one to two levels darker (C4–C5). Thorax, nota and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxaalwayscarinated,bearingonefinesetaand furnished with 3–4 spines on carina and 1–3 on ventral side; fore trochanter with 5–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 3; Figs 30–31, 37). Size: the workers of I. bulbifrons are among the medium sized to the largest of the genus Isognathotermes (with large overlapping on several other species: Fig. 30). Head capsule: weakly sclerotised (except mandibles). Antennae: generally 14.5 articles, 14 in workers from incipient colonies. Labrum: cupola shaped. Left mandible: apical tooth well developedwithasharptipwhenfresh;marginalteeththreeinnumber,firstmarginalwelldevelopedbut European Journal of Taxonomy 1024: 1–197 (2025) 52 Fig. 36 (continued on next page). Isognathotermes bulbifrons (Sjöstedt, 1924) and junior synonym species: soldiers. Lateral and dorsal views of a soldier’s head capsule, ventral view of its mandibles, and dorsal view of its labrum. A. From type colony of Cubitermes bulbifrons Sjöstedt, 1924 (DJ 0298). B. From type colony of Cubitermes heghi Sjöstedt, 1924 (DJ 0290). C. From type colony of Mirotermes (Cubitermes) kemneri Emerson, 1928 (DJ 0297). D. From type colony of Cubitermes gibbifrons Sjöstedt, 1924 (DJ 0280). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 53 with a blunt tip even when fresh, second marginal faint (visible as an undulated edge but disappearing in worn mandibles), third marginal with a blunt tip; premolar tooth with its proximal end generally hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed with a sharp tip whenfresh;marginalteethtwoinnumber;firstmarginalwelldevelopedwithasharptipwhenfresh; second marginal smaller and with a blunt tip even when fresh; molar tooth bearing a ventral rounded flangeandendingposteriorlyinakindofheel.Thorax: pronotum sellate, as wide as 64 to 78% of head width. Fore coxaflangedventrallyresultinginasharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, are wide and bear at that place a high density of rather short bristles on a globular bulge; supporting bristles are generally numerous: 22–38 on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre of abdomen, shortly lobed (three, rarely two or four, small lobes, sometimes only sketched). Fig. 36 (continued). E. From “C. aff. subarquatus spC” (DJ 0621). F. From an incipient colony of I. bulbifrons (DJ 0725). G. From type colony of Mirotermes (Cubitermes) congoensis Emerson, 1928 (DJ 0299), probably also an incipient colony of I. bulbifrons (Sjöstedt, 1924) (labrum somewhat distorted by dessication). European Journal of Taxonomy 1024: 1–197 (2025) 54 Fig. 37 (continued on next page). Isognathotermes bulbifrons (Sjöstedt, 1924) and junior synonym species: soldiers and workers. PC1s of soldier’s and worker’s enteric valves, worker’s caecum and foreleg. A. From type colony of Cubitermes bulbifrons Sjöstedt, 1924 (DJ 0298). B. From type colony of Cubitermes heghi Sjöstedt, 1924 (DJ 0290), the downstream end of worker’s PC1 is twisted. C. From type colony of Mirotermes (Cubitermes) kemneri Emerson, 1928 (DJ 0299). D. From type colony of Cubitermes gibbifrons Sjöstedt, 1924 (DJ 0280). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 55 Chorology-ecology This species has been collected in the northwestern Congolian lowland forest and the Atlantic equatorial coastal forest ecoregions (Cameroon, Gabon, DRC and Angola) up to about 300 km from the Atlantic coast (Fig. 38). Molecular data The species I. bulbifrons corresponds to the Cubitermes “spC” in Roy et al. 2006 and Hellemans et al. 2021, proposed on basis of the COII gene. Our present sampling includes full mitogenomes from Gabonese samples previously published under the appellation “Cubitermes aff. subarquatus spC” by Roy et al. (2006), which we herein formally assign to I. bulbifrons. Ten mitogenomes of I. bulbifrons collected from Gabon and Cameroon are published alongside this work (GenBank accessions: see Supp.file3 and ‘Material examined’). Overall, mitogenomes exhibit less than Fig. 37 (continued). E. From “Cubitermes aff. subarquatus spC” (DJ 0621). F. From an incipient colony of I. bulbifrons (Sjöstedt, 1924) (DJ 0726). G. From type colony of Mirotermes (Cubitermes) congoensis Emerson, 1928 (DJ 0299 & 0484), which is, probably, also an incipient colony of I. bulbifrons. European Journal of Taxonomy 1024: 1–197 (2025) 56 2% dissimilarity with each other (Supp.file4 with the samples DJ 0621 and DJ P158 being the most dissimilar). Of the ten samples sequenced, nine belonged to the large form of I. bulbifrons and only one (DJ P246) to the former I. gibbifrons (the medium-sized form of I. bulbifrons). Isognathotermes finitimus (Schmitz, 1916) Figs 5, 13–20, 22, 26–33, 39–41, distribution map: Fig. 38; Table 4 CubitermesfinitimusSchmitz,1916:120–124,figs1–2. Cubitermes speciosus Sjöstedt, 1924b: 256. Syn. nov. Mirotermes (Cubitermes) subarquatusEmerson,1928:510–511,pl.XXIXfig.55. Cubitermesfinitimus– Sjöstedt 1926: 221–226. — Snyder 1949: 159. — Bouillon & Vincke 1971: 269. — Krishna et al.2013:1920.—Josens&Deligne2019:60–61,figs11,16. Cubitermes subarquatus – Krishna et al. 2013: 1938. Isognathotermesfinitimus– Hellemans et al. 2021: 231–233. Diagnosis AsalreadypointedoutbyH.Schmitz(1916),asoldieroranimagoalonedoesnotallowaconfident identification.Indeed,thisspeciesisdifficulttoidentifyfromitsmorphologysinceitisinamedium position in the genus Isognathotermes (blue ellipse in the middle of Fig. 22). It is obviously easier to identify this species from its mitogenome: I.finitimus makes a clade well apart from the planifrons clade (Hellemans et al. 2021: 231). Fig. 38. Distribution map of Isognathotermes bulbifrons (Sjöstedt, 1924) (red dots), I.finitimus (Schmitz, 1916) (green dots), and I. congoensis (Emerson, 1928) (blue triangles). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 57 If molecular data are not available, the best recognition is reached by a combination of worker’s EVA, soldiers’ mandibles, and geographical origin. The worker has a finitimus EVA and is among the medium-sized workers of the genus Isognathotermes (Fig. 30). The soldier is also medium sized in the genus Isognathotermes (Fig. 28; SHdL = 2.70–3.45 mm), and its EVA can generally be recognized as a finitimus EVA. The forehead has little, or no prominence, and theupperprofileisonlyslightlyconcave.IncomparisonwithI. planifrons, it has, on average, a higher acceleration of the mandible curvature: ln(SMlpR) - ln(SMldR) = 1.28–2.42 (0.89–2.28 in I. planifrons), that means: mandibles less curved at the base and more so at the tip. In I. planifrons, the soldier has on average slightly more curved mandibles. The imago is also medium sized (Fig. 26) in the genus Isognathotermes (IHdW = 1.47–1.71 mm). This medium-sized species can be confused with several other species with a finitimus EVA: I. planifrons and I. bulbifrons (I. phalloides sp. nov. and I. phallicaecalis sp. nov. have also similar sizes and morphologies but they can be distinguished easily by their caecum). Isognathotermes finitimuscan also be characterized by its ecology and chorology: it has always been found in continental forests east of longitude 15°E (but the I.finitimus and I. planifrons areas overlap in the south-west of CAR (Figs 38, 47); other species with a finitimus EVA can be found in this area: I. magniplanifrons sp. nov. with distinctly larger soldiers or I. phallicaecalis sp. nov. and I. phalloides sp. nov. with a characteristic, different caecum. Etymology The epithet finitimus from the Latin finitimus (bordering, close to) doubtless refers to the proximity of C.finitimus with both C. fungifaber and C. zenkeri, discussed at length by Schmitz in the original description. Material examined Sixty samples from 24 locations. Of the 35 old museum samples examined, nine samples were initially labelled as Cubitermesfinitimus, four as C. fungifaber, one as C. fungifaber var. elongata, one as C. loubetsiensis, six as C. minitabundus, 11 as C. speciosus, two as C. subarquatus, and one as Cubitermes sp. Syntype of Cubitermes finitimus Schmitz, 1916 DEMOCRATICREPUBLICOFTHECONGO•♀(queen);Stanleyville[=Kisangani];0°31′N, 25°12′E;before1904;H.Kohlleg.;studycode:DJ0291;initiallyC.finitimus→C. fungifaber; AMNH. Syntypes of Cubitermes speciosus Sjöstedt, 1924 DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♀(queen);Moto;2°54.47′N, 29°24.85′E;1923;L.Burgeonleg.;studycode:DJ0061;initiallyC. speciosus in RMCA; BE RMCA INS.Iso.059178. Krishna et al. (2013: 1937) mention that other syntype samples are deposited in AMNH and PPRI, not examined. European Journal of Taxonomy 1024: 1–197 (2025) 64 S truCture (measurements in Table 4; Figs 30, 41). Size: the workers of I.finitimus are, on average, medium sized in the genus Isognathotermes (but with large overlapping on several other species: Fig. 30). Head capsule weakly sclerotised (except mandibles). Antennae 14.5 articles, rarely 14. Labrum: cupola shaped. Left mandible: apical tooth well developed with a sharp tip when fresh; marginal teeth three innumber,firstmarginalwelldevelopedbutwithablunttipevenwhenfresh,secondmarginalfaint (visible as an undulated edge and disappearing in worn mandibles), third marginal with a blunt tip; premolar tooth with its proximal end generally hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apicaltoothwelldevelopedwithasharptipwhenfresh;marginalteethtwoinnumber;firstmarginal well developed with a sharp tip when fresh; second marginal smaller and with a blunt tip even when fresh;molartoothbearingaventralroundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum sellate, as wide as 64–74% of head width. Fore coxaflangedventrallyresultinginasharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of Fig. 40. Isognathotermesfinitimus (Schmitz, 1916) and junior synonym species: soldiers. Lateral and dorsal views of a soldier’s head capsule, ventral view of its mandibles, and dorsal view of its labrum. A. From a non-type colony of Isognathotermesfinitimus (DJ 0655). B. From type colony of Cubitermes speciosus Sjöstedt, 1924 (DJ 0061). C. From type colony of Cubitermes subarquatus Sjöstedt, 1926 (DJ 0295). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 65 abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, are wide and bear at that place a very high density of rather short bristles on a globular bulge (Fig. 41); supporting bristles are generally numerous: 22–29 on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre ofabdomen,shortlylobed(twotofivesmalllobes,sometimesonlysketched). Fig. 41. Isognathotermesfinitimus (Schmitz, 1916) and junior synonym species: soldiers and workers. PC1s of soldier’s and worker’s enteric valves; worker’s caecum and foreleg. A. From a non-type colony of Isognathotermesfinitimus (Schmitz, 1916) (DJ 0655). B. From type colony of Cubitermes speciosus Sjöstedt, 1924 (DJ 0061). C. From type colony of Cubitermes subarquatus Sjöstedt, 1926 (DJ 0295). European Journal of Taxonomy 1024: 1–197 (2025) 66 Chorology-ecology The geographic distribution of I.finitimus is linked with the continental forests of central Africa; it includes the central and northeastern Congolian lowland forest and the Victoria Basin forest-savanna mosaic ecoregions (Fig. 38). Molecular data Seven mitogenomes of I. finitimus are published alongside this work (GenBank accessions: see Supp.file3 and ‘Material examined’). They are characterized by less than 1.05% dissimilarity with each other (Supp.file4), with the sample DJ 0741 being the most dissimilar. Phylogenetic reconstructions based on full mitogenomes placed them in a sister relationship to the species I. ugandensis and I. minitabundus, to which they exhibit less than 2% dissimilarity. Remarks In the absence of genetic information, I.finitimusisoftendifficulttoascertainasitsmorphologyplacesit in the middle of the genus Isognathotermes; for the species with a finitimus EVA alone, there are partial overlaps with I. bulbifrons and I. planifrons, and also with I. phallicaecalis sp. nov., and I. phalloides sp. nov. but these last two are distinguished by their caecum. Integrative taxonomy comes into its own here: in particular, chorology is a valuable aid: two samples –DJ0655andDJ0656–collectedatYangambi(TshopoProvince,DRC),wereinitiallyidentifiedas I. gibbifrons on the basis of their morphology (although in disagreement with the chorology of this species). Mitogenome-based phylogenetic reconstructions subsequently placed these samples in I.finitimus. Isognathotermes fungifaber (Sjöstedt, 1896) Figs 1, 3–4, 6, 26–31, 33, 42–44, distribution map: Fig. 45; Tables 5–6 Eutermes fungifaber Sjöstedt, 1896: 297 (alate imago only). Mirotermes (Cubitermes) schmidti Emerson,1928:520–521,fig.62. Mirotermes (Cubitermes) banksi Emerson,1928:522–523,fig.63. Mirotermes (Cubitermes) comstocki Emerson,1928:525,fig.64. Eutermes fungifaber – Sjöstedt 1900: 143–149, pl. IV (all castes). Mirotermes (Cubitermes) fungifaber—Sjöstedt1913:369,plX,3.—Emerson1928:517–519,fig.60. Cubitermes fungifaber – Silvestri 1914: 91. — Sjöstedt 1926: 218–225. — Snyder 1949: 159. — Bouillon & Vincke 1971: 269. — Krishna et al. 2013: 1921–1922. — Josens & Deligne 2019: 60. Cubitermes banksi – Ruelle 1992: 501. — Krishna et al. 2013: 1913. Cubitermes comstocki – Ruelle 1992: 501. — Krishna et al. 2013: 1918. Cubitermes schmidti – Ruelle 1992: 501. — Krishna et al. 2013: 1935. Cubitermes sp. affinis subarquatus “spA” – Roy et al. 2006: 4–5. Cubitermes sp. affinis subarquatus “spD” – Roy et al. 2006: 4–5. Isognathotermes fungifaber – Hellemans et al. 2021: 233. Diagnosis The worker has a fungifaber EVA (Fig. 4) but in 2% of the samples examined, it has an EVA intermediate between the fungifaber and finitimus patterns. The worker itself and its enteric valve are among the smallest in the genus Isognathotermes (Fig. 31). The soldier is among the smallest in the genus Isognathotermes; (SHdL = 2.37–3.11 mm, Fig. 28); its EVA generally looks like a muneris EVA and is among the smallest in the genus Isognathotermes EVAs. In some samples, however, the soldier is as large as the smallest soldiers of I. severus. The soldier has, JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 67 along with I. planifrons, the most evenly curved mandibles from base to tip: ln(SMlpR) - ln(SMldR) = 0.85–1.88. The imago is, on average and with that of I. phalloides sp. nov., the smallest in the genus Isognathotermes; (IHdW = 1.40–1.61 mm, Fig. 26). Thisspeciesisalsodefinedbyitsecologyandchorology:ithasalwaysbeenfoundinevergreenforests from RCI to Gabon at less than 300 km from the Atlantic coast (Fig. 45 but see later, ‘Supplementary material of dubious I. fungifaber’). Etymology The name fungifaber from the Latin fungus (mushroom) and faber (artisan) doubtless refers to the building of mushroom-shaped epigeous nests. Material examined One hundred twenty-four samples from 44 locations (plus six samples of “dubious I. fungifaber” from fivelocations).Ofthe64oldmuseumsamplesexamined,49wereinitiallylabelledasC. fungifaber, one as C. fungifaber var. elongata, four as C. banksi, one as C. comstocki, three as C. gaigei, three as C. kemneri, two as C. modestior, and one as C. schmidti. Of the six samples of “dubious I. fungifaber”, four were initially labelled as C. fungifaber andtwonotidentified. This species also includes C. aff. subarquatus “spA” and “spD” (in Roy et al. 2006). Syntypes of Eutermes fungifaber Sjöstedt, 1896 CAMEROON•soldier,worker,♀(alate),♀(queen);Mbongé;4°32.18′N,9°6.67′E;Oct.1891; Y. Sjöstedt leg.; study code: DJ 0271; initially Eutermes fungifaber;NHMM•soldier,worker,♀(queen); Mbongé;4°32.18′N,9°6.67′E;27Oct.1891;Y.Sjöstedtleg.;studycode:DJ0272;initiallyEutermes fungifaber;AMNH•worker,♀(alate);Mbongé(?);4°32.18′N,9°6.67′E;1891;Y.Sjöstedtleg.;study code: DJ 0965; initially Eutermes fungifaber ex typis; RBINS. Krishna et al. (2013: 1921) mention that other syntype samples are deposited in NHRM, not examined. Paratypes of Mirotermes (Cubitermes) banksi Emerson, 1928 CAMEROON•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0287; initially Mirotermes (C.) banksi→C. fungifaber;AMNH•soldier,worker;Bipindi;3°5′N,10°24.5′E; 1920; G. Zenker leg.; study code: DJ 0097; initially C. banksi in RMCA; BE RMCA INS.Iso.059210. Krishna et al. (2013: 1913) mention that the holotype and paratypes are deposited in UMMZ, not examined. Paratypes of Mirotermes (Cubitermes) comstocki Emerson, 1928 CAMEROON•soldier,worker,♀(queen);Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;study code: DJ 0273; initially Mirotermes (C.) comstocki→C. fungifaber;AMNH•soldier,worker,♀(alate); Bipindi?;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0278;initiallyC. comstocki→ C. fungifaber;AMNH•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode: DJ 0121; initially C. comstocki in RMCA; BE RMCA INS.Iso.059212. Krishna et al. (2013: 1918) mention that the holotype (soldier) and paratypes are deposited in UMMZ, not examined, and that other paratypes are deposited in the Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, not examined. European Journal of Taxonomy 1024: 1–197 (2025) 68 Paratypes of Mirotermes (Cubitermes) schmidti Emerson, 1928 CAMEROON•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0275; initially C. schmidti→C. fungifaberinAMNH•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920; G. Zenker leg.; study code: DJ 0124; initially Mirotermes (C.) schmidti in RMCA; BE RMCA INS. Iso.059213 Other material examined CAMEROON•soldier;Abonando[=Ossidinge];5°54′N,9°8′E;nodate;G.Mansfeldleg.;study code: DJ N123; initially C. fungifaber;AMNH•soldier,worker,♀(alate);Mungo;5°12′N,9°31′E; 1903; Rohde leg.; study code: DJ 0269; initially C. fungifaber var. elongata; AMNH • soldier, worker; Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0963;initiallyEutermes fungifaber; RBINS•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0964; initially Eutermes fungifaber;RBINS•soldier;RéserveduNyong;3°50′N,10°50′E;6Dec.1949; J. Birkett-Smith and J. Dahl leg.; study code: DJ U036; initially C. fungifaber; NHMUK 13671854 • soldier;Edea;3°29′N,9°50′E;Jul.–Sep.1973;N.M.Collinsleg.;studycode:DJU033;initially C. fungifaber;NHMUK13671851•soldier;Edea;3°29′N,9°50′E;Jul.–Sep.1973;N.M.Collinsleg.; study code: DJ U039; initially C. fungifaber;NHMUK13671847•soldier;Edea;3°29′N,9°50′E;Jul.– Sep. 1973; N.M. Collins leg.; study code: DJ U040; initially C. fungifaber; NHMUK 13671850 • soldier; Edea;3°29′N,9°50′E;Jul.–Sep.1973;N.M.Collinsleg.;studycode:DJU041;initiallyC. fungifaber; NHMUK13671848•soldier;Edea;3°29′N,9°50′E;Jul.–Sep.1973;N.M.Collinsleg.;studycode: DJ U042; initially C. fungifaber;NHMUK13671846•soldier;Mbalmayo;3°30′N,11°31′E;1Dec. 1962; G. Becker leg.; study code: DJ U065; initially C. fungifaber; NHMUK 13671852 • soldier, worker;Mamfe–Ikomroad;5°47′N,8°58′E;18Sep.1966;W.Wilkinsonleg.;studycode:DJ0718; initially C. gaigei;NHMUK13671886•worker,♂(king);Edea;3°29′N,9°50′E;Jul.–Sep.1973; N.M. Collins leg.; study code: DJ 0649; initially C. fungifaber; NHMUK 13671846 • soldier, worker, ♀(alate);Ebodjié;2°38′N,9°53′E;Nov.1991;A.Dejeanleg.;studycode:DJ0096;initiallyC. banksi inRMCA;BERMCAINS.Iso.059211•soldier;Akok;3°53′N,11°57′E;ca1995;P.Eggletonet al. leg.; study code: DJ U049; initially C. fungifaber;NHMUK13671877•soldier;Akok;3°53′N,11°57′E;ca 1995; P. Eggleton et al. leg.; study code: DJ U050; initially C. fungifaber; NHMUK 13671876 • soldier; Akok;3°53′N,11°57′E;ca1995;P.Eggletonet al. leg.; study code: DJ U052; initially C. fungifaber; NHMUK13671879•soldier;Akok;3°53′N,11°57′E;ca1995;P.Eggletonet al. leg.; study code: DJ U053; initially C. fungifaber;NHMUK13671880•soldier,♀(alate);Ebogo;3°23′N,11°28′E; ca 1995; P. Eggleton et al. leg.; study code: DJ U045; initially C. fungifaber; NHMUK 13671874 • soldier;Ebogo;3°23.5′N,11°28′E;ca1995;P.Eggletonet al. leg.; study code: DJ U068; initially C. kemneri;NHMUK13672024•soldier;Ebogo;3°23.5′N,11°28′E;ca1995;P.Eggletonet al. leg.; study code: DJ U069; initially C. kemneri;NHMUK13672025•soldier;Ebogo;3°31′N,11°30′E;ca 1995; P. Eggleton et al. leg.; study code: DJ U092; initially C. banksi; NHMUK 13671831 • soldier, ♂(king),♀(queen);Eboufek;3°31′N,11°30′E;ca1995;P.Eggletonet al. leg.; study code: DJ U051; initially C. fungifaber;NHMUK13671875•soldier,worker,♂(king);Eboufek;3°30′N,11°53′E; ca 1995; P. Eggleton et al. leg.; study code: DJ 0651; initially C. kemneri; NHMUK 13672023 • soldier,worker,♂(alate);Eboufek;3°30′N,11°53′E;ca1995;P.Eggletonet al. leg.; study code: DJ 0707; initially C. banksi;NHMUK13671828•soldier,♂(king);Ekombitié;3°28′N,11°31′E; ca 1995; P. Eggleton et al. leg.; study code: DJ U048; initially C. fungifaber; NHMUK 13671872 • soldier;Mbalmayo;3°27′N,11°29′E;ca1995;P.Eggletonet al. leg.; study code: DJ U047; initially C. fungifaber;NHMUK13671871•soldier;Mbalmayo;3°27′N,11°29′E;Feb.1996;P.Eggleton et al. leg.; study code: DJ U044; initially C. fungifaber; NHMUK 13671870 • soldier; Mbalmayo; 3°27′N,11°29′E;Mar.1996;P.Eggletonet al. leg.; study code: DJ U046; initially C. fungifaber; NHMUK13671859•soldier;Mbalmayo;3°27′N,11°29′E;Aug.1996;P.Eggletonet al. leg.; study code: DJ U043; initially C. fungifaber;NHMUK13671873•soldier;Nsimi;3°10′N,11°58′E;Nov. 1996; M. Harry leg.; study code: DJ P136; GenBank no PQ679252 (mitogenome); MNHN EP9869 • JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 69 soldier;Nsimi;3°10′N,11°58′E;Nov.1996;M.Harryleg.;studycode:DJP137;MNHNEP9870• soldier;Nsimi;3°10′N,11°58′E;Nov.1996;M.Harryleg.;studycode:DJP138;MNHNEP9871• soldier;Nsimi;3°10′N,11°58′E;Nov.1996;M.Harryleg.;studycode:DJP139;MNHNEP9872• soldier;Nsimi;3°10′N,11°58′E;Nov.1996;M.Harryleg.;studycode:DJP140;MNHNEP9873• soldier,worker,♂(alate);Makak;3°38′N,11°4′E;27Nov.2013;J.Birkett-SmithandJ.Dahlleg.; study code: DJ 0650; initially C. fungifaber;NHMUK13671853•soldier,worker,♂(alate);Bipindi; 3°5′N,10°24.5′E;23Nov.2016;P.Akamaleg.;studycode:DJ0452;GenBanknosMN646713(COI), MN685915 (COII), MN685976 (28S), PQ679181 (mitogenome); BE RMCA INS.Iso.059200 • soldier, worker;Bipindi;3°5′N,10°24.5′E;23Nov.2016;P.Akamaleg.;studycode:DJ0468;GenBankno PQ679188(mitogenome);BERMCAINS.Iso.059196•soldier,worker;Bipindi;3°5′N,10°24.5′E;23 Nov. 2016; P. Akama leg.; study code: DJ 0469; GenBank no PQ679195 (mitogenome); BE RMCA INS. Iso.059195•soldier,worker,♀(alate);Mbongé;4°32.2′N,9°6.7′E;30Nov.2016;P.Akamaleg.;study code: DJ 0450; GenBank nos MN646712 (COI), MN685914 (COII), MN685975 (28S); BE RMCA INS. Iso.059194•soldier,worker;Mbongé;4°32.2′N,9°6.7′E;30Nov.2016;P.Akamaleg.;studycode: DJ0451;GenBanknoPQ679193(mitogenome);BERMCAINS.Iso.059202•soldier,worker,♂(alate); Mbongé;4°32.2′N,9°6.7′E;30Nov.2016;P.Akamaleg.;studycode:DJ0466;GenBanknoPQ679246 (mitogenome);BERMCAINS.Iso.059198•soldier,worker,♂(alate);Mbongé;4°32.2′N,9°6.7′E;30 Nov. 2016; P. Akama leg.; study code: DJ 0467; GenBank no PQ679226 (mitogenome); BE RMCA INS. Iso.059203•soldier,worker,♀(queen);Ebogo;3°22.894′N,11°27.862′E;23May2017;Y.Roisinleg.; study code: DJ 0506; GenBank nos MN646714 (COI), MN685916 (COII), MN685977 (28S); BE RMCA INS.Iso.059206•soldier,worker;Ebogo;3°22.872′N,11°27.796′E;6Jun.2017;Y.Roisinleg.;study code: DJ 0521; GenBank no PQ679222 (mitogenome); BE RMCA INS.Iso.059205 • soldier, worker; Mbalmayo;3°28.841′N,11°34.646′E;6Jun.2017;Y.Roisinleg.;studycode:DJ0520;GenBankno PQ679185 (mitogenome); BE RMCA INS.Iso.059207 CÔTED’IVOIRE•soldier;BancoN.P.;5°23′N,4°3′W;1Jan.1934;P.-P.Grasséleg.;studycode: DJP199;MNHNEP9849•soldier;BancoN.P.;5°23′N,4°3′W;8Jan.1934;P.-P.Grasséleg.;study code:DJP153;MNHNEP9844•soldier,worker;BancoN.P.;5°24′N,4°3′W;9Jan.1934;P.-P. Grassé leg.; study code: DJ 0203; initially C. fungifaber in MNHN; MNHN EP9840 • soldier; Banco N.P.;5°23′N,4°3′W;Jan.1939;P.-P.Grasséleg.;studycode:DJP157;MNHNEP9845•soldier, ♀(queen);BancoN.P.;5°23′N,4°3′W;6Feb.1947;C.Noirotleg.;studycode:DJP194;MNHN EP9848•soldier,♂(king);Adiopodoumé;5°19.75′N,4°8′W;22May1947;C.Noirotleg.;study code:DJP193;MNHNEP9847•soldier;BancoN.P.;5°19′N,4°10′W;26Jul.1947;C.Noirotleg.; studycode:DJP325;MNHNEP9863•soldier;Mambo;5°46′N,4°3′W;19Oct.1947;C.Noirotleg.; studycode:DJP324;MNHNEP9862•soldier;Mambo;5°46′N,4°3′W;19Oct.1947;C.Noirotleg.; studycode:DJP333;MNHNEP9948•soldier;Mambo;5°46′N,4°3′W;20Oct.1947;C.Noirotleg.; studycode:DJP334;MNHNEP9949•soldier;Yapo;5°44′N,4°5′W;10Oct.1947;C.Noirotleg.; studycode:DJP326;MNHNEP9864•soldier,worker,♀(alate);PetitYaporéserveforestière;5°46′N, 4°8′W;22Aug.1953;M.Lüscherleg.;studycode:DJ0277;initiallyC. fungifaber; AMNH • soldier; BancoN.P.;5°24′N,4°3′W;6Dec.1959;C.Noirotleg.;studycode:DJP211;MNHNEP9860•soldier; BancoN.P.;5°24′N,4°3′W;25Dec.1959;C.Noirotleg.;studycode:DJP208;MNHNEP9857• soldier,worker,♂(alate);nearAbidjan;5°23′N,4°3′W;ca1960;C.Noirotleg.;studycode:DJ0268; initially C. fungifaber;AMNH•soldier;BancoN.P.;5°24′N,4°3′W;17Jan.1960;C.Noirot(?)leg.; studycode:DJP203;MNHNEP9852•soldier;BancoN.P.;5°24′N,4°3′W;17Jan.1960;C.Noirot (?)leg.;studycode:DJP205;MNHNEP9854•soldier;BancoN.P.;5°24′N,4°3′W;17Jan.1960;C. Noirot(?)leg.;studycode:DJP207;MNHNEP9856•soldier;BancoN.P.;5°24′N,4°3′W;17Jan. 1960;C.Noirotleg.;studycode:DJP209;MNHNEP9858•soldier;BancoN.P.;5°24′N,4°3′W;17 Jan.1960;C.Noirotleg.;studycode:DJP210;MNHNEP9859•soldier;BancoN.P.;5°24′N,4°3′W; 30Jan.1960;C.Noirot(?)leg.;studycode:DJP201;MNHNEP9850•soldier;BancoN.P.;5°24′N, 4°3′W;30Jan.1960;C.Noirot(?)leg.;studycode:DJP204;MNHNEP9853•soldier;BancoN.P.; European Journal of Taxonomy 1024: 1–197 (2025) 70 5°24′N,4°3′W;20Mar.1960;C.Noirotleg.;studycode:DJP329;MNHNEP9866•soldier;Banco N.P.;5°24′N,4°3′W;7May1960;C.Noirot(?)leg.;studycode:DJP202;MNHNEP9851•soldier, ♂(alate);BancoN.P.;5°24′N,4°3′W;7May1960;C.Noirot(?)leg.;studycode:DJP206;MNHN EP9855•soldier;BancoN.P.;5°24′N,4°3′W;12Jun.1960;C.Noirotleg.;studycode:DJP330; MNHNEP9867•soldier;BancoN.P.;5°24′N,4°3′W;17Jun.1960;C.Noirotleg.;studycode: DJP336;MNHNEP9951•soldier;BancoN.P.;5°24′N,4°3′W;9Oct.1960;C.Noirotleg.;studycode: DJP327;MNHNEP9865•soldier;BancoN.P.;5°24′N,4°3′W;9Oct.1960;C.Noirotleg.;studycode: DJP331;MNHNEP9868•soldier,♂(king);Abidjan;5°20′N,3°59′W;29Dec.1960;C.Noirotleg.; studycode:DJP347;MNHN•soldier,♂(alate);Adiaké;5°22′N,3°19.7′W;15Apr.1963;C.Noirot leg.;studycode:DJP348;MNHN•soldier;BancoN.P.;5°23′N,4°3′W;21Aug.1968;G.Josens leg.; study code: DJ U001; initially C. modestior; NHMUK 13671927 • soldier, worker; Banco N.P.; 5°24′N,4°3′W;21Aug.1968;G.Josensleg.;studycode:DJ0202;initiallyC. modestior in RMCA; BERMCAINS.Iso.059204•soldier,worker;Ahoutoué;5°28′N,3°45′W;9Aug.1969;Vincentleg.; studycode:DJ0229;BERMCAINS.Iso.059209•soldier,worker;BancoN.P.;5°23.005′N,4°3.341′W; 17 Feb. 2015; G. Josens leg.; study code: DJ 0412; GenBank nos MN646711 (COI), MN685913 (COII), MN685974 (28S), PQ679172 (mitogenome); BE RMCA INS.Iso.059208. EQUATORIALGUINEA•soldier;PuntaFrailes;3°47′N,8°43′E;ca1894;R.M.Downesleg.;study code: DJ U110; initially C. gaigei;NHMUK13671887•soldier,worker,♀(alate);PuntaFrailes; 3°47′N,8°43′E;Oct.1901;L.Fealeg.;studycode:DJ0311;initiallyC. fungifaber; MCGD. GABON•soldier;Mekambo;1°1′N,13°56′E;Jan.1957;P.-P.GrasséandC.Noirotleg.;studycode: DJP167;MNHNEP9846•soldier,worker;PisteduBouéni;0°13′N,11°48′E;1Jan.1957;P.-P.Grassé and C. Noirot leg.; study code: DJ 0855; MNHN EP9843 • soldier, worker; Piste du Bouéni, km 53; 0°44′N,13°12′E;1Jan.1957;P.-P.GrasséandC.Noirotleg.;studycode:DJ0853;MNHNEP9841• soldier,worker,♂(king),♀(queen);forêtdensedeDjidji;0°13′N,11°48′E;25Jan.1957;P.-P.Grassé andC.Noirotleg.;studycode:DJ0854;MNHNEP9842•soldier,worker;LaLopéN.P.;0°15′S, 11°35′E;9Mar.1998;M.Harryleg.;studycode:DJP242;MNHNEP9875•soldier,worker;LaLopé N.P.;0°12.7′S,11°33.5′E;9Mar.1998;M.Harryleg.;studycode:DJ0623;GenBanknosDQ127302 (COII), DQ246527 (ITS2), PQ679189 (mitogenome); initially C. aff. subarquatus “spA” (cf. Roy et al. 2006);MNHNEP9878•soldier,worker;Doda(northofLaLopéN.P.);0°4.5′S,11°25.5′E;10Mar. 1998; M. Harry leg.; study code: DJ 0625; GenBank nos DQ246541 (COII), DQ246526 (ITS2) initially C. aff. subarquatus “spD” (cf. Roy et al. 2006);MNHNEP9879•soldier,♀(queen);LaLopéN.P.; 0°15′S,11°35′E;13Mar.1998;M.Harryleg.;studycode:DJP243;MNHNEP9876•soldier,worker; LaLopéN.P.;0°12.7′S,11°33.5′E;13Mar.1998;M.Harryleg.;studycode:DJ0626;GenBanknos DQ127299 (COII), DQ246529 (ITS2), PQ679214 (mitogenome); initially C. aff. subarquatus “spA” (cf. Roy et al. 2006);MNHNEP9880•soldier;LaLopéN.P.;0°9′S,11°36′E;6Mar.1998;M. Harryleg.;studycode:DJP232;MNHNEP9874•soldier,worker;Bitam;2°5′N,11°30′E;15Apr. 2017; G. Trembleau leg.; study code: DJ 0456; BE RMCA INS.Iso.059197 • soldier, worker; Bitam; 2°5′N,11°30′E;15Apr.2017;G.Trembleauleg.;studycode:DJ0457;BERMCAINS.Iso.059201• soldier;Bitam;2°5′N,11°30′E;15Apr.2017;G.Trembleauleg.;studycode:DJ0458;BERMCA INS.Iso.059199•soldier,worker;Nkobissimo[=Nkolmengboua?];2°14.3′N,11°29.25′E;15Apr. 2017; G. Trembleau leg.; study code: DJ 0453; GenBank no PQ679216 (mitogenome); BE RMCA INS. Iso.059193•soldier,worker;Ipassa;0°30.66′N,12°48′E;27Jan.2025;J.Šobotnikleg.;studycode: DJ 0974; BE RMCA INS.Iso.059949. GHANA•soldier,♀(queen);BobiriForestReserve;6°40′N,1°21′W;21Feb.1959;W.A.Sandsleg.; study code: DJ U114; initially C. gaigei; NHMUK 13671881. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 71 NIGERIA•soldier;Ijebu–Oderoad;6°50′N,3°54′E;2May1950;G.C.Webbleg.;studycode: DJ N126; initially C. fungifaber;AMNH•soldier;NorthofLagos;6°49′N,3°13′E;11Feb.1955;W.V. Harris leg.; study code: DJ U063; initially C. fungifaber; NHMUK 13671865 • soldier; Mofu River forest reserve;6°10′N,7°10′E;15Feb.1955;W.V.Harrisleg.;studycode:DJU062;initiallyC. fungifaber; NHMUK13671864•soldier;PortHarcourt;4°46′N,7°1′E;5Dec.1955;D.Kayleg.;studycode: DJ U057; initially C. fungifaber;NHMUK13671868•soldier;Sapele;5°53′N,5°41′E;31Jan.1956; D. Kay leg.; study code: DJ U056; initially C. fungifaber; NHMUK 13671866 • soldier; Obanikoro; 6°33′N,3°22′E;8Jan.1957;W.Wilkinsonleg.;studycode:DJU034;initiallyC. fungifaber; NHMUK13671861•soldier;Ugo;6°5′N,6°0′E;11Jan.1957;W.Wilkinsonleg.;studycode: DJ U061; initially C. fungifaber;NHMUK13671860•soldier,worker;Ilaro(near)?;7°26′N,3°5′E;6 Apr. 1957; W. Wilkinson leg.; study code: DJ 0549; initially C. fungifaber;NHMUK•soldier,♀(queen); Calabar-Mamferoad;5°17′N,8°34′E;22Apr.1957;W.Wilkinsonleg.;studycode:DJU035;initially C. fungifaber;NHMUK13671863•soldier;PortHarcourt–Owerriroad;5°11′N,6°52′E;19Jun.1957; W. Wilkinson leg.; study code: DJ U064; initially C. fungifaber; NHMUK 13671867 • soldier, worker; PortHarcourt–Owerriroad;5°9.5′N,6°51′E;19Jun.1957;W.Wilkinsonleg.;studycode:DJ0548; initially C. fungifaber;NHMUK•soldier;Mamuforestreserve;6°11′N,7°10′E;28Feb.1958;W.A. Sands leg.; study code: DJ U058; initially C. fungifaber; NHMUK 13671862 • soldier; Enugu–Otukpo road;6°45′N,7°28′E;5Mar.1958;W.A.Sandsleg.;studycode:DJU055;initiallyC. fungifaber; NHMUK13671858•soldier;Ayangba;7°30′N,7°10′E;6Mar.1958;W.A.Sandsleg.;studycode: DJ U059; initially C. fungifaber;NHMUK13671857•soldier;Ijebu–Oderoad;6°49′N,3°55′E; 12 Dec. 1959; W.A. Sands leg.; study code: DJ U060; initially C. fungifaber; NHMUK 13671859. Supplementary material of dubious I. fungifaber Four samples from the CAR, near Bangui, and two from eastern DRC (Fig. 45) show a soldier’s morphology entirely consistent with that of I. fungifaber. As these samples come from semi-deciduous forest and forest galleries (which is not characteristic of I. fungifaber) and as it was not possible to sequence them, these six samples, are presented here as “dubious, possibly cryptic I. fungifaber”. The distance between Bangui and the nearest harvesting point in Gabon is around 500 km, and between Bangui and eastern DRC, the distance is around 1300 km. Of the six old museum samples examined, four samples were initially labelled as C. fungifaber and two notidentified. CENTRALAFRICANREPUBLIC•soldier;routeMbaïki–Bagandou;3°52′N,17°52′E;21Jun. 1948; P.-P. Grassé and C. Noirot leg.; study code: DJ P188; MNHN EP9825 • soldier; Boukoko; 3°54′N,17°55′E;2Jul.1948;P.-P.GrasséandC.Noirotleg.;studycode:DJP189;MNHNEP9826• soldier;Bangui;4°27′N,18°32′E;1975;Beckerleg.;studycode:DJU037;initiallyC. fungifaber; NHMUK13671856•soldier;Bangui;4°27′N,18°32′E;1975;Beckerleg.;studycode:DJU038; initially C. fungifaber; NHMUK 13671855. DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♀(queen);“AltoUele,foresta”; 2°30′N,29°30′E;[nodate];S.Patrizileg.;studycode:DJ0312;initiallyC. fungifaber in MCGD • soldier,♀(alate);Epulu;1°24′N,28°34′E;15May1948;A.Emersonleg.;studycode:DJN129; initially C. fungifaber in AMNH. Historical review ThealateimagofromBonge[=Mbongé],Cameroon,wasbrieflydescribedbySjöstedt(1896:297) under the name Eutermes fungifaber, mentioning it as very close to Eutermes mordax (Smeathman, 1781). European Journal of Taxonomy 1024: 1–197 (2025) 72 Fouryearslater,Sjöstedt(1900:143–149)providedmoredetaileddescriptions(textandfigures)ofall castes and nest. Sjöstedt (1926: 218–225) included Cubitermes fungifaber in imagines' and soldiers' keys of Cubitermes species and inserted it in a “fungifaber-Gruppe” of species with a not forward humped soldier’s frons. Emerson (1928: 517–519) referred to this species as Mirotermes (Cubitermes) fungifaber; he provided further descriptions and measurements of all castes, based on samples collected by G. Zenker in Cameroon. Snyder (1949: 159) catalogued this species under the name Cubitermes fungifaber in the sub-family Termitinae. Bouillon & Vincke (1971: 269) described the enteric valve of C. fungifaberasbelongingtothefirstof three types, the “simple type” without any spatula. Cubitermes fungifaber was considered as a senior synonym of (a) C. banksi, (b) C. comstocki and (c) C. schmidti (Emerson unpublished “Card catalog”; Ruelle 1992: 501; Krishna et al. 2013: 1913, 1918, 1935). These three species are somewhat smaller than C. fungifaber, but synonymies are compatible with their enteric valve patterns (Josens & Deligne 2019: 39–42). To obtain genetic sequences of I. fungifaber, one of us (PA) went and collected samples at Mbongé, type location of I. fungifaber, and at Bipindi, type location of I. banksi, I. comstocki and I. schmidti; some of the soldiers in those samples were as small as the soldiers of C. comstocki and Hellemans et al. (2021: 233)confirmedtheirsynonymiesandplacedthespeciesintherestoredgenusIsognathotermes. Cubitermes fungifaber was considered a senior synonym of C. fungifaber var. elongata (Krishna et al. 2013: 1923) and a possible senior synonym of C. planifrons (Emerson in his unpublished “card catalog”, quoted by Krishna et al. 2013: 1931) but these synonymies are rejected because the two taxa proposed as junior synonyms do not have enteric valves of the fungifaber pattern, but well of the finitimus one (Josens & Deligne 2019: 42–44). Cubitermes aff. subarquatus “spA” and Cubitermes aff. subarquatus “spD” were mentioned by Roy et al. (2006) in La Lopé National Parc, Gabon; on a genetical base they were considered as cryptic species. Hellemans et al. (2021: 231) placed these species in the restored genus Isognathotermes as synonyms of I. fungifaber. As already mentioned, the geographic distribution of I. fungifaber is clearly dependant on humid, forest environments. In at least one documented case, its geographic distribution has been changing during the second half of the 20th century, possibly in relation with global and local climate change. Isognathotermes fungifaber used to be common in the Banco National Park near Abidjan, RCI: see the publications by Noirot et al. (1986), Han & Lepage (1991), and personal observation (GJ, in 1970); however, nowadays, thisnationalparkisalmosttotallyincludedwithinthecityofAbidjan,whichpresumablyinfluencesthe local climate. Moreover, the annual rainfall in Côte d’Ivoire has been declining by about 20% during the last decades, mainly during the late sixties and early seventies (Servat et al. 1999), possibly linked with hugedeforestation.Thismightexplainthattwoofus(GJandYR)couldhardlyfindasinglenestofthis species in 2015 in the Banco National Park. Redescription Imago Colour. Head capsule: well sclerotised, fresh samples very dark, C7–C8 (C6–C7 in long preserved imagines); fontanelle concolorous or almost so with head capsule. Postclypeus C6–C7 slightly paler (one level) than head capsule. Antennae C5–C6 without any difference between proximal and distal JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 73 articles. Thorax: pronotum C6–C8 (C5–C7 in long preserved imagines), as postclypeus, generally one level paler than head capsule; mesoand metanotum C5–C7, sometimes somewhat paler than pronotum. Legs C3–C5; tibia usually slightly (one level) darker than femur. Wings hyaline with brown to grey tinge (Cf3–Cf4), anterior veins darker. Abdomen: tergites C5–C7. Sternites appreciably paler in middle (C3– C4) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat40×,sometimes onlyat80×.Legsverypilose,furnished(amongnumerousfinesetae)withsomestrongersetae:5–12 on the carina of fore coxa and 1–8 on the ventral side of fore coxa and trochanter; tibia pilose fore, mid, and hind tibia furnished with 30–40 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. S truCture (measurements in Table 5; Fig. 42). Size: the imagines of I. fungifaber are, on average, among the smallest of the genus Isognathotermes (Fig. 26). Head capsule: compound eyes shortly oval; ocelli Fig. 42. Isognathotermes fungifaber (Sjöstedt, 1896) and junior synonym species: imagines. Lateral and dorsal views of an imago’s head capsule, and dorsal view of this imago’s mandibles. A. Alate female from the type colony of Eutermes fungifaber Sjöstedt, 1896 (DJ 0271). B. Queen from the type colony of Mirotermes (Cubitermes) comstocki Emerson, 1928 (DJ 0273). C. Alate male from a non-type colony of I. fungifaber (Sjöstedt, 1896) (DJ 0268). European Journal of Taxonomy 1024: 1–197 (2025) 80 the Northwestern Congolian lowland forests ecoregions. This distribution partly resembles that of I. planifrons (that has a different EVA). However, some samples of “dubious I. fungifaber” come from the northeastern Congolian lowland forests ecoregion without it being possible to guarantee the true species of these samples. Molecular data Thirteen mitogenomes of I. fungifaber are published alongside this work (GenBank accessions: see Supp.file3 and ‘Material examined’). These were collected from RCI, Cameroon, and Gabon. Most samples exhibit less than 1% dissimilarity with each other (Supp.file4); except for sample DJ 0451 being the most dissimilar (1.50%) collected in one of the type localities of the species, and for sample DJ 0412, collected at the westernmost part of its distribution (1.32%). Our phylogenetic reconstructions based on the COIIgene(FigureSF2)includessamplesidentifiedas“Cubitermes aff. subarquatus spA” (DJ 0623 and DJ 0626) and “spD” (DQ246541, DJ 0625) of Roy et al. (2006). The two mitogenomes of “spA” samples were successfully re-sequenced from the samples having produced the COII sequences published under accession DQ127302 and DQ127299 but not that of the “spD” sample. Therefore, the cryptic species status of the “spD” proposed by Roy et al. (2006) cannot be discussed here. Remarks Isognathotermes fungifaber is quite variable in size and much more in soldiers and workers than in imagines: we can deduct from Table 5 that variability in head width for I. fungifaber is 14% in imagines, but 31% in soldiers and 28% in workers The soldiers of several samples have an intermediate morphology between I. fungifaber and I. severus (having the same kind of EVA): the easiest way to distinguish them is their origin since they seem to be Fig. 45. Distribution map of Isognathotermes fungifaber (Sjöstedt, 1896) (blue dots); dubious I. fungifaber (blue empty triangles); I. severus (Silvestri, 1914) (red dots); I. severus modestior (Silvestri, 1914) (yellow square). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 81 mutually exclusive. This is linked with their preferred habitat: on the one hand, I. fungifaber seems to be restricted to evergreen forests with, however, one known exception: DJ 0625, that was proposed as a cryptic species (“spD”) by Roy et al. 2006: it was collected in the Doda gallery forest, surrounded with savannahs, north of La Lopé National Park, Gabon. On the other hand, I. severus is common in savanna landscapes of West and Central Africa (from Gambia to CAR) but also in orchards, secondary forests and, in some regions, it is also found in evergreen forest but only in places where I. fungifaber is absent as for example in RCI near the border with Liberia. Isognathotermes magniplanifrons Josens & Deligne sp. nov. urn:lsid:zoobank.org:act:6AAAE9B8-6907-4716-BD3D-CB10E171B2D8 Figs 26–31, 46, distribution map: Fig. 47; Table 7 Diagnosis The worker has a finitimus EVA and is among the large workers of the genus Isognathotermes (WHdW =1.30–1.42mm,Fig.30)butratherdifficulttodistinguishfromthatofotherspecies. The soldier has generally a recognizable finitimus EVA; it is, on average, and with the soldier of I. bulbifrons, the largest of the Isognathotermes species with a finitimus EVA (SHdL = 2.98–3.77 mm, Fig. 28), with more curved mandibles (SMlc = 0.24–0.36 mm, Fig. 29), as in I. planifrons; its head is slightly bulbous (SHdC = 0.0–0.07 mm), less than that of I. bulbifrons and similar to I. planifrons. The imago is, on average, and with the imago of I. bulbifrons, the largest in the genus Isognathotermes with a finitimus EVA (IHdW = 1.62–1.78 mm, Fig. 26); but its mandibular apico-marginal distance is generally smaller (IMlAmD = 0.20–0.24 mm, Fig. 27) than in I. bulbifrons (IMlAmD = 0.20–0.30 mm in I. bulbifrons). Isognathotermes magniplanifrons sp. nov., is therefore morphologically close to I. bulbifrons but their chorology is different: to date, I. magniplanifrons is only known from the north-east of the DRC (HautUele and Kivu provinces). Etymology The name magniplanifrons is from the Latin magnus (large) and the species name planifrons, referring to the resemblance with I. planifrons but with larger individuals in all castes. Material examined Twenty-four samples from two locations. Of the 24 old museum samples, one was initially labelled as C. minitabundus, one as C. speciosus, and 22 as Cubitermes sp. Holotype DEMOCRATICREPUBLICOFTHECONGO•soldier;Irangi;1°54′S,28°27′E;7Sep.1970;A.Wabo leg.; study code: DJ 0920; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059253. Paratypes DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♂(alate),♀(queen);samedataasfor holotype; BE RMCA INS.Iso.059935. Other material examined DEMOCRATICREPUBLICOFTHECONGO•soldier,worker;Moto;3°2′N,29°30′E;1923;L. Burgeon leg.; study code: DJ 0070; initially C. speciosus in RMCA; BE RMCA INS.Iso.059258 • European Journal of Taxonomy 1024: 1–197 (2025) 82 soldier,worker;Irangi;1°54′S,28°27′E;10Apr.1952;A.Waboleg.;studycode:DJ0896;initially C. minitabundusinRMCA;BERMCAINS.Iso.059256•soldier,worker,♂(alate);Irangi;1°54′S, 28°27′E;4Sep.1970;A.Waboleg.;studycode:DJ0894;initiallyCubitermes sp. in RMCA; BE RMCA INS.Iso.059252•soldier,worker,♂(king);Irangi;1°54′S,28°27′E;4Sep.1970;A.Waboleg.; study code: DJ 0919; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059251 • soldier, worker, ♂(king),♀(queen);Irangi;1°54′S,28°27′E;6Sep.1970;A.Waboleg.;studycode:DJ0929;initially Cubitermes sp.inRMCA;BERMCAINS.Iso.059254•soldier;Irangi;1°54′S,28°27′E;21Sep.1970; A. Wabo leg.; study code: DJ B262; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059238 • soldier;Irangi;1°54′S,28°27′E;21Sep.1970;A.Waboleg.;studycode:DJB263;initiallyCubitermes sp.inRMCA;BERMCAINS.Iso.059239•soldier;Irangi;1°54′S,28°27′E;21Sep.1970;A.Wabo leg.; study code: DJ B264; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059240 • soldier; Irangi;1°54′S,28°27′E;21Sep.1970;A.Waboleg.;studycode:DJB265;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059241•soldier;Irangi;1°54′S,28°27′E;20Sep.1970;A.Wabo leg.; study code: DJ B267; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059236 • soldier; Irangi;1°54′S,28°27′E;20Sep.1970;A.Waboleg.;studycode:DJB268;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059237•soldier;Irangi;1°54′S,28°27′E;20Sep.1970;A.Wabo leg.; study code: DJ B269; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059243 • soldier; Irangi;1°54′S,28°27′E;25Jan.1972;A.Waboleg.;studycode:DJB272;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059246•soldier;Irangi;1°54′S,28°27′E;28Feb.1972;A.Wabo leg.; study code: DJ B303; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059249 • soldier; Irangi;1°54′S,28°27′E;13Mar.1972;A.Waboleg.;studycode:DJB304;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059250•soldier;Irangi;1°54′S,28°27′E;31Mar.1972;A.Wabo leg.; study code: DJ B261; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059235 • soldier; Irangi;1°54′S,28°27′E;13Mar.1972;A.Waboleg.;studycode:DJB274;initiallyCubitermes sp.inRMCA;BERMCAINS.Iso.059248•soldier;Irangi;1°54′S,28°27′E;1Apr.1972;A.Wabo leg.; study code: DJ B273; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059247 • soldier; Irangi;1°54′S,28°27′E;9May1972;A.Waboleg.;studycode:DJB270;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059244•soldier,♀(alate);Irangi;1°54′S,28°27′E;1972?;A.Wabo leg.; study code: DJ B316; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059255 • soldier, ♀(alate);Irangi;1°54′S,28°27′E;1972?;A.Waboleg.;studycode:DJB317;initiallyCubitermes sp. inRMCA;BERMCAINS.Iso.059257•soldier;Irangi;1°54′S,28°27′E;11Sep.1972;A.Waboleg.; study code: DJ B266; initially Cubitermes sp. in RMCA; BE RMCA INS.Iso.059242 • soldier; Irangi; 1°54′S,28°27′E;15Sep.1972;A.Waboleg.;studycode:DJB271;initiallyCubitermes sp. in RMCA; BE RMCA INS.Iso.059245. Historical review This species is described here. It was collected in 1923 in the Haut-Uele Province, DRC (and misidentified),andin1970inKivu,DRC.Thisspeciesisknownfrom24samples,23ofwhichcome from the same locality. Description Imago Colour. Head capsule: well sclerotised, dark, C6–C7; fontanelle concolorous or almost so with head capsule. Postclypeus C5–C7 concolorous or slightly paler (one level) than head capsule. Antennae C4– C6 without any difference between proximal and distal articles. Thorax: pronotum C5–C6, as head capsule or slightly paler (one level); mesoand metanotum C4–C6, as pronotum or slightly paler. Legs C4–C5. Wings hyaline with brown to grey tinge (Cf3), anterior veins darker. Abdomen: tergites C4–C6. Sternites appreciably paler in middle (C3–C4) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 83 Setation. Head capsule with some prominent setae, mainly near the eyes, and a higher density of shorter, finersetaeeverywhere.Labrumandpostclypeuswithsomeprominentsetaemixedwithshorterones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyatmagnification50×ormore).Thorax: pronotum with prominent setae mainly on margins and many shorter ones in middle; mesoand metanotum without anyvisiblesetaeorwithsomefine,palesetae,arrangedinamedio-longitudinalstrip,visibleat40×; generally three to four larger setae on metanotum. Legsverypilose,furnished(amongnumerousfine setae)withsomefinespines:6–10onthecarinaofforecoxaand0–2ontheventralside;tibiapilose; fore, mid, and hind tibia furnished with 20–30 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 7, Fig. 46). Size: the imagines of I. magniplanifrons sp. nov. are, on average, rather large (but not the largest of the genus Isognathotermes) (IHdW = 1.62–1.78 mm). Head capsule: compound eyes nearly round; fontanelle generally a tiny elongate marking; ocelli nearly round to oval removed from eyes by a distance about equal to 0.7–1.1 ocellus small diameter. Antennae:16articlesonalateindividuals,shortenedbyamputationbyfivetosixarticlesinqueensand kings. Labrum: cupola shaped. Left mandible with mandibular apico-marginal distance clearly smaller (IMlAmD = 0.20–0.24 mm) than in I. bulbifrons (Fig. 27); apical tooth longer and more prominent than firstmarginal;marginalteeththreeinnumberbutsecondoneonlysuggestedbyaslightundulationof edgebetweenfirstandthirdmarginalteeth;onlytheapicaltoothisacuteinunwornspecimens;premolar tooth with proximal end obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible with apicaltoothlongerandmoreprominentthanfirstmarginal;marginalteethtwoinnumber;firstmarginal tooth well developed with a sharp tip when fresh; second marginal tooth smaller and with a blunt tip evenwhenfresh;molartoothbearingaventralroundedflangeandendingposteriorlyinakindofheel. Thorax: pronotum appreciably wider than long and slightly narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxa flangedventrallyresultinginasharpcarina.Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 2–3 and 12–13 branches, respectively. Soldier Colour. Head capsule generally C6–C7, paler (C5) in a long-preserved sample; with a gradient from a darkerfronstoapalerback(e.g.,C6→C4).Gulamentumconcolorouswithhead.Antennaeandlabrum somewhat paler (1–2 levels) than head capsule. Mandibles dark (C8) with or without a slight clearing on their bases (one palette level) which is generally the same colour as frons. Thorax, nota and legs paler than head capsule (C4–C5). Abdomen grey to red-brown owing to digestive bolus, sometimes with a yellow tinge on tergites. Setation. Head capsule with few scattered setae; on frons a dense bunch of hair-like setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Labrum always with 5–7 large setae on each lobe. Thorax: proand mesonotum with some setae located mainly on margins. Legs: fore coxa furnished with 1–2 spines on carina and not any one on ventral side; trochanter generally with some long lined-up setae, sometimes with two spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively; all tibiae furnished with a row of 6–15 spines. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 7; Fig. 46). Size: the soldiers of I. magniplanifrons sp. nov. are, on average, the largest of the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised European Journal of Taxonomy 1024: 1–197 (2025) 84 and appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a narrowing near posterior third or fourth; from antennal sockets sides converge more or less clearly towards bases of mandibles. In profile:upperprofileslightlyconcave(asinI. planifrons, much less than in I. bulbifrons); frons with no hump overhanging the fontanelle. Gulamentum in ventral view always more or less constricted in its posterior half, with sides of anterior part either forming an acute widening or even a kindofearoneachside;generally,withaflatposteriorpartfromsideview.Antennae:of15articles. Labrum:alwaysdeeplybifurcateandwiderthanlong,withlyre-shapedsides;lobesangular,withfine, whitish, or translucent tips; anterior margin concave. Mandibles: sabre-like; inner edges smooth with one small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible generally slightly more curved than left. Thorax: pronotum sellate, as wide as 57–63% of head width, with generally entire anterior and posterior margins. Fore coxaflangedventrallyresultinginacarina.Gut: enteric valve seating Fig. 46. Isognathotermes magniplanifrons Josens & Deligne sp. nov.: imago, soldier, and worker. A. Lateral and dorsal views of the head capsule, and dorsal view of mandibles of an alate male from the type colony of I. magniplanifrons (DJ 0920). B. Lateral and dorsal views of the head capsule; ventral view of mandibles; and dorsal view of labrum of a soldier from the type colony of I. magniplanifrons (DJ 0920). C. PC1s of soldier’s and worker’s enteric valves; caecum and foreleg of this worker from the type colony of I. magniplanifrons. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 85 on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions showing trilateral symmetry: the odd cushions are on average 14% longer than the even cushions, generally without any hump or with humps weakly developed; however, the pilosity becoming abruptly very dense shows the place where a hump is expected (Fig. 46); secondary cushions wide at the upstream end narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, best seen in ventral view, near centre of abdomen, lobed (2–4 small lobes). Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always one to two levels darker (C4–C5). Thorax, nota and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Table 7. Isognathotermes magniplanifrons Josens&Delignesp.nov.:rangesofsignificantmeasuresin the three castes, in alphabetical orders of the “Code” column. Variable *Code *Range Type Imagines (n = 8) Raw measures (mm) Eye: large diameter IEyD0.43–0.48 0.47 Head: width across the eyes IHdW 1.62–1.78 1.71 Left mandible: A-m1 distance IMlAmD 0.20–0.24 0.21 Ocellus: large diameter IOcD0.17–0.21 0.19 Postclypeus: width IPcW 0.77–0.85 0.81 Pronotum: maximal width IPnW 1.40–1.63 1.56 Hind tibia: length IT3L 1.99–2.29 2.17 Wing: length (n = 4) IWgL 14.2–14.3 NA Index Left apico-marginal index IMlAmD/IMlmmD 1.16–1.46 1.29 Soldiers (n = 24) Raw measures (mm) Head: upper sagitta SHdC 0.00–0.07 0.02 Head: length SHdL 2.98–3.77 3.62 Head: width SHdW 2.07–2.49 2.40 Left mandible: lesser sagitta SMlc 0.24–0.36 0.32 Left mandible: ventral length SMlL 2.45–2.99 2.81 Hind tibia: length ST3L 1.77–2.01 1.91 Indices Head elongation index SHdL/SHdW 1.37–1.59 1.51 Left mandible: apical curvature index SMlc/SMlL 0.09–0.13 0.11 Mandibles: curvature symmetry SMlc/SMrc 0.76–1.10 0.96 Workers (n = 6) Raw measures (mm) Head: width WHdW 1.30–1.42 1.32 Left mandible: A-m1 distance WMlAmD 0.19–0.21 0.19 Left mandible: total length WMlL 0.63–0.68 0.64 Hind tibia: length WT3L 1.39–1.57 1.43 Valve: PC average length WVP-AvL 0.61–0.70 0.61 Valve: PC average width WVP-AvW 0.08–0.10 0.08 Valve: SC average length WVS-AvL 0.48–0.52 0.48 Valve: SC average width WVS-AvW 0.22–0.28 0.22 Index Valve: odd PC elongation index WVPOdd-Elg 6.54–9.38 7.80 *Abbreviations:seedefinitionsinMaterialandmethods. European Journal of Taxonomy 1024: 1–197 (2025) 86 Setation. Head capsule and postclypeus with few, erect scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxaalwayscarinated,bearingonefinesetaand furnished with 3–5 spines on carina and 1–2 on ventral side; fore trochanter with 6–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. S truCture (measurements in Table 7, Fig. 46). Size: the workers of I. magniplanifrons sp. nov. are, on average, among the largest of the genus Isognathotermes (but with large overlapping on several other species: Fig. 30). Fore coxaflangedventrallyresultinginasharpcarina.Head capsule: weakly sclerotised (except mandibles). Antennae: 14.5 articles. Labrum: cupola shaped. Left mandible: apical toothwelldevelopedwithasharptipwhenfresh;marginalteeththreeinnumber,firstmarginalwell developed but with a blunt tip even when fresh, second marginal faint (visible as an undulated edge), third marginal with a blunt tip; premolar tooth with its proximal end hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed with a sharp tip when fresh; marginal teeth twoinnumber;firstmarginalwelldevelopedwithasharptipwhenfresh;secondmarginalsmallerand withablunttipevenwhenfresh;molartoothbearingaventralroundedflangeandendingposteriorlyin a kind of heel. Thorax: pronotum sellate, as wide as 70% of head width. Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, are wide and bear at that place a high density of rather short bristles on a globular bulge; supporting bristles are generally numerous: 20–38 on each side of the odd PCs; secondary cushions are wide at the upstream Fig. 47. Distribution map of Isognathotermes acristatus Josens & Deligne sp. nov. (green dots); I. magniplanifrons Josens & Deligne sp. nov. (pink diamonds); I. planifrons (Sjöstedt, 1924) (blue empty triangles); I.similifinitimusJosens & Deligne sp. nov. (red triangle). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 87 end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre of abdomen, shortly lobed (3–4 small lobes). Chorology-ecology The geographic distribution of I. magniplanifrons sp. nov. is linked with the northeastern Congolian lowland forests ecoregion (Fig. 47). Molecular data No genetic sequence is currently available. Isognathotermes minitabundus (Sjöstedt, 1913) Figs 2, 8–12, 26–31, 33, 48, distribution map: Fig. 49; Table 8 Eutermes (Cubitermes) minitabundus Sjöstedt, 1913: 368–369 (soldier only). Eutermes (Trinervitermes) carbo – Sjöstedt 1924a: 42 (the alate imago described under this name actually belonged to Cubitermes minitabundus). Isognathotermes minitabundus –Sjöstedt1926:216–217,fig.48.—Hellemanset al. 2021: 233. Cubitermes minitabundus –Snyder1949:161.—Harris1958:13–14,figs20–23.—Williams1966: 90–92,figs6,22,38,54,72.—Bouillon&Vincke1971:269.—Krishnaet al. 2013: 1927. — Josens & Deligne 2019: 60–61. Diagnosis This species is very close to I. ugandensis (and I. severus). The worker has a fungifaber EVA (Fig. 4) but in 3% of the samples examined, it has an EVA intermediate between the fungifaber and finitimus patterns. It is among the medium-sized workers of the genus Isognathotermes (Fig. 30). As in I. ugandensis, the premolar tooth on left mandible is more apparent than in most other species. The soldier is among the large-sized soldiers in the genus Isognathotermes (Fig. 28), on average somewhat larger than that of I. ugandensis; it has a left mandible very slightly curved to almost straight at the base and generally less curved than the right mandible (SMlc/SMrc = 0.51–1.03, with a weaker asymmetry than in I. ugandensis: SMlc/SMrc = 0.92–1.14), resulting in a low soldiers’ left mandible apical curvature index (Fig. 29); its head is generally clearly bulbous (but this is shared with I. ugandensis and I. severus, and also with I. bulbifrons which has a finitimus EVA). The imago is among the mediumto large-sized imagines in the genus Isognathotermes (Figs 26, 65); the eyes and ocelli are relatively small, as a consequence, the eye to ocellus minimal distance index is high: IEyOcD/IOcd = 1.16–1.61 (vs 0.54–1.58 in I. ugandensis). The premolar tooth on left mandible is better seen than in most other species (but this is shared with I. severus and I. ugandensis). Thisspeciesisalsodefinedbyitsecologyandchorology:itisthesouthernmostspeciesofthegenus Isognathotermes, it has been found in forest-savannah mosaics and woodlands (miombo) to the south and east of the Congolian forests (Fig. 49). Etymology The epithet minitabundus from the Latin minitabundus (threatening) probably refers to a supposed threat. European Journal of Taxonomy 1024: 1–197 (2025) 88 Material examined Thirty-six samples from 15 locations. Of the 24 old museum samples, 18 were initially labelled as C. minitabundus, four as C. ugandensis, one as Eutermes fungifaber and one as Cubitermes sp. Syntype of Eutermes (Cubitermes) minitabundus (Sjöstedt, 1913) DEMOCRATICREPUBLICOFTHECONGO•soldier;Lumata;12°0.05′S,27°31′E;6Jun.1912;J. Bequaert leg.; study code: DJ 0129; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059280. Other material examined DEMOCRATICREPUBLICOFTHECONGO•soldier,worker;HemptineSaintBenoît[=Bunkonde]; 6°18′S,22°31′E;1912;P.Callewaertleg.;studycode:DJ0140;initiallyC. minitabundus in RMCA; BERMCAINS.Iso.059284•soldier,worker,♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;21 Jan. 1912; P. Callewaert leg.; study code: DJ 0094; initially Eutermes fungifaber in RMCA; BE RMCA INS.Iso.059274•soldier,worker;HemptineSaintBenoît[=Bunkonde];6°18′S,22°32′E;26Jan. 1912; P. Callewaert leg.; study code: DJ 0015; initially C. minitabundus in RMCA; BE RMCA INS. Iso.059286•soldier,worker,♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;26Oct.1921;P. Callewaert leg.; study code: DJ 0139; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059283 • soldier,worker,♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;26Oct.1921;P.Callewaertleg.; study code: DJ 0157; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059276 • soldier, worker, ♀(alate),♂(alate),♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;27Oct.1921;P.Callewaert leg.; study code: DJ 0144; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059285 • soldier, worker,♀(alate),♂(alate),♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;27Oct.1921;P. Callewaert leg.; study code: DJ 0155; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059278 • soldier,worker,♀(alate),♂(alate),♀(queen);Luluabourg[=Kananga];5°53′S,22°26′E;27Oct. 1921; P. Callewaert leg.; study code: DJ 0156; initially C. minitabundus in RMCA; BE RMCA INS. Iso.059275•soldier,worker,♀(alate);Luluabourg[=Kananga];5°53′S,22°26′E;27Oct.1921;P. Callewaert leg.; study code: DJ 0158; initially C. minitabundus in RMCA; BE RMCA INS.Iso.059277 • soldier,worker,♀(alate);Luluabourg[=Kananga];5°53′S,22°26′E;27Oct.1921;P.Callewaert leg.; study code: DJ 0728; initially C. minitabundus; AMNH • soldier, worker; Upemba N.P., Lusinga; 8°56.4′S,27°8′E;17Jul.1947;G.F.DeWitteet al. leg.; study code: DJ 0137; initially C. minitabundus inRMCA;BERMCAINS.Iso.059282•soldier,worker,♂(king),♀(queen);UpembaN.P.,Lusinga; 8°56.4′S,27°8′E;17Jul.1947;G.F.DeWitteet al. leg.; study code: DJ 0138; initially C. minitabundus inRMCA;BERMCAINS.Iso.059281•soldier,worker,♂(king);Keyberg(Lubumbashi);11°47′S, 27°25′E;21Apr.1948;A.Emersonleg.;studycode:DJ0729;initiallyC. minitabundus in AMNH • soldier,worker,♂(king);Likasi;10°59.3′S,26°4.27′E;1Dec.1971;P.Vinckeleg.;studycode: DJ 0898; initially C. ugandensisinRMCA;BERMCAINS.Iso.059271•soldier,worker,♂(alate); KundelunguP.N.;10°27′S,27°42′E;15Oct.1972;P.Vinckeleg.;studycode:DJ0899;initially Cubitermes sp.inRMCA;BERMCAINS.Iso.059272•soldier,worker;Kipopo;11°33′S,27°21′E; 2 Nov. 1972; P. Vincke leg.; study code: DJ 0908; initially C. ugandensis in RMCA; BE RMCA INS. Iso.059273•soldier,worker;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.3′E;11Feb.2011;G. Josens leg.; study code: DJ 0010; BE RMCA INS.Iso.059279 • soldier, worker; Kisangwe, Mikembo sanctuary;11°29.1′S,27°39.3′E;Jun.2016;P.Kasangijleg.;studycode:DJ0348;GenBanknos MN646704 (COI), MN685906 (COII), MN685967 (28S), PQ679238 (mitogenome); BE RMCA INS. Iso.059270•soldier;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.3′E;3Jun.2016;P.Kasangij leg.; study code: DJ B008; BE RMCA INS.Iso.059259 • soldier; Kisangwe, Mikembo sanctuary; 11°29.1′S,27°39.3′E;3Jun.2016;P.Kasangijleg.;studycode:DJB009;GenBanknoPQ679225 (mitogenome);BERMCAINS.Iso.059260•soldier;Kisangwe,Mikembosanctuary;11°29.1′S, 27°39.3′E;3Jun.2016;P.Kasangijleg.;studycode:DJB010;BERMCAINS.Iso.059261•soldier; Kisangwe,Mikembosanctuary;11°29.1′S,27°39.3′E;3Jun.2016;P.Kasangijleg.;studycode: DJB011;BERMCAINS.Iso.059262•soldier;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.18′E; JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 89 14 Jun. 2016; P. Kasangij leg.; study code: DJ B012; BE RMCA INS.Iso.059263 • soldier; Kisangwe, Mikembosanctuary;11°29.1′S,27°39.18′E;14Jun.2016;P.Kasangijleg.;studycode:DJB014; BERMCAINS.Iso.059264•soldier;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.2′E;14Jun. 2016; P. Kasangij leg.; study code: DJ B017; BE RMCA INS.Iso.059265 • soldier; Kisangwe, Mikembo sanctuary;11°29.1′S,27°39.2′E;14Jun.2016;P.Kasangijleg.;studycode:DJB018;BERMCAINS. Iso.059266•soldier;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.2′E;22Jun.2016;P.Kasangij leg.; study code: DJ B019; BE RMCA INS.Iso.059267 • soldier; Kisangwe, Mikembo sanctuary; 11°29.1′S,27°39.2′E;22Jun.2016;P.Kasangijleg.;studycode:DJB020;BERMCAINS.Iso.059268• soldier;Kisangwe,Mikembosanctuary;11°29.1′S,27°39.2′E;2Jul.2016;P.Kasangijleg.;studycode: DJ B021; BE RMCA INS.Iso.059269. ZAMBIA•soldier,worker;Kitwe,MwekeraForestreserve;12°52′S,28°21′E;25Jan.1956; W.G.H. Coaton leg.; study code: DJ 0696; initially C. minitabundus; NHMUK 13671922 • soldier, worker;Samfya;11°22′S,29°33′E;27Jan.1957;W.G.H.Coatonleg.;studycode:DJ0665;initially C. ugandensis;NHMUK13672010•soldier,worker;Chembe;11°57.5′S,28°44′E;28Jan.1957; W.G.H. Coaton leg.; study code: DJ 0685; initially C. minitabundus; NHMUK 13671920 • soldier; Ndola–Kitweroad;12°59′S,28°24.5′E;30Jan.1957;W.G.H.Coatonleg.;studycode:DJ0694; initially C. minitabundus;NHMUK13671921•soldier,worker;Kasama–Mpikaroad;11°0′S,31°0′E; 19 Dec. 1969; M.G. Bingham leg.; study code: DJ 0695; initially C. minitabundus; NHMUK 13671925 • soldier,worker;Chililabombwe;12°23′S,27°50′E;22Dec.1970;M.G.Binghamleg.;studycode: DJ 0693; initially C. minitabundus; NHMUK 13671926. Historical review Sjöstedt (1913: 368–369) described the soldier of his species under the name Eutermes (Cubitermes) minitabundus. Schmitz (1916: 119) referred to this species under the name Cubitermes minitabundus. Sjöstedt (1924a: 42) described the imago of Eutermes (Trinervitermes) carbo that was in fact the imago of Cubitermes minitabundus (see Sands 1965: 98 and Krishna et al. 2013: 1858). Sjöstedt (1926: 216–217) transferred the species in a new, monotypic genus (Isognathotermes). He providedfiguresofthesoldierandadescriptionofimagoandworker. Snyder (1949: 161) catalogued this species under the name Cubitermes minitabundus and housed it in the sub-family Termitinae. Harris(1958:13–14)providedmeasurementsandfiguresofimagoandsoldieronbasisofspecimens collected in the Upemba National Park (Haut-Katanga Province, DRC). Williams (1966: 90–92) provided a detailed redescription of imago and soldier along with measurements andfigures. Bouillon & Vincke (1971: 269) described the enteric valve of C. minitabundusasbelongingtothefirst of three types, the “simple type” without any spatula. Krishna et al. (2013: 1927) referred to this species under the name Cubitermes minitabundus and housed it in the sub-family Cubitermitinae. Josens & Deligne (2019: 39–42) placed this species within the fungifaber valve pattern group. Hellemans et al. (2021: 233) placed this species in the restored genus Isognathotermes. European Journal of Taxonomy 1024: 1–197 (2025) 96 head capsule; mesoand metanotum C6 slightly paler than head. Legs C4. Abdomen: tergites C6. Sternites appreciably paler in the middle (C3–C5) with both sides darker (C5–C6) than anterior. Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat20–40×;sometimes with one or two large setae on posterior lobe. Legsverypilose,furnished(amongnumerousfine setae) with 7–11 stronger setae on the carina of fore coxa and 1–3 on the ventral side of fore coxa and trochanter; tibia pilose, fore, mid, and hind tibia furnished with 30–40 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. S truCture (measurements in Table 9, Fig. 50). Size: the imagines of I. modicus sp. nov. are, on average, medium sized in the genus Isognathotermes (Fig. 26). Head capsule: compound eyes nearly round; ocelli shortly oval, removed from eyes by a distance equal to 0.9–1.3 ocellus small diameter; fontanelle Fig. 50. Isognathotermes modicus Josens & Deligne sp. nov.: imago, soldier, and worker. A. Lateral and dorsal views of the king’s head capsule from the type colony of I. modicus (DJ 0862), and dorsal view of this imago’s mandibles. B. Lateral and dorsal views of a soldier’s head capsule from the type colony, ventral view of its mandibles, and dorsal view of its labrum. C. PC1s of soldier’s and worker’s enteric valves from the type colony, and caecum and foreleg of this worker. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 97 generally a tiny round or elongate marking. Antennae: shortened to 12 articles by amputation of probably four articles in queens and kings. Labrum: cupola shaped, wider than long. Left mandible with apical toothmediumsizedinthegenus(Fig.27)andalwaysmoreprominentthanfirstmarginal;marginalteeth threeinnumberbutsecondoneonlysuggestedbyanundulationofedgebetweenfirstandthirdmarginal teeth; only the apical tooth is acute in unworn specimens; premolar tooth almost totally obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible with apical tooth always more prominent than firstmarginal;marginalteethtwoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhen fresh; second marginal tooth smaller and with a blunt tip even when fresh; molar tooth bearing a ventral roundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum appreciably wider than long Table 9. Isognathotermes modicus Josens&Delignesp.nov.:rangesofsignificantmeasuresinthethree castes,inalphabeticalordersofthe“Code”column;fivesamplesfromonelocation. Variable *Code *Range Type Imagines (n = 5) Raw measures (mm) Eye: large diameter IEyD0.41–0.46 0.45 Head: width across the eyes IHdW 1.56–1.65 1.64 Left mandible: A-m1 distance IMlAmD 0.21–0.24 0.22 Ocellus: large diameter IOcD0.15–0.18 0.17 Postclypeus: width IPcW 0.77–0.82 0.79 Pronotum: maximal width IPnW 1.38–1.48 1.41 Hind tibia: length IT3L 1.82–1.97 1.90 Wing: length (n = 0) IWgL NA NA Index Left apico-marginal index IMlAmD/IMlmmD 1.28–1.78 1.41 Soldiers (n = 5) Raw measures (mm) Head: upper sagitta SHdC 0.00–0.05 0.01 Head: length SHdL 2.42–2.66 2.58 Head: width SHdW 1.80–1.89 1.88 Left mandible: lesser sagitta SMlc 0.22–0.26 0.25 Left mandible: ventral length SMlL 1.93–2.16 2.01 Hind tibia: length ST3L 1.41–1.52 1.51 Indices Head elongation index SHdL/SHdW 1.32–1.44 1.37 Left mandible: apical curvature index SMlc/SMlL 0.11–0.13 0.12 Mandibles: curvature symmetry SMlc/SMrc 0.88–1.12 1.03 Workers (n = 3) Raw measures (mm) Head: width WHdW 1.07–1.13 1.13 Left mandible: A-m1 distance WMlAmD 0.17–0.18 0.18 Left mandible: total length WMlL 0.52–0.57 0.56 Hind tibia: length WT3L 1.12–1.20 1.20 Valve: PC average length WVP-AvL 0.45–0.48 0.45 Valve: PC average width WVP-AvW 0.06–0.08 0.08 Valve: SC average length WVS-AvL 0.36–0.39 0.36 Valve: SC average width WVS-AvW 0.16–0.22 0.17 Index Valve: odd PC elongation index WVPOdd-Elg 4.85–7.20 5.16 *Abbreviations:seedefinitionsinMaterialandmethods. European Journal of Taxonomy 1024: 1–197 (2025) 98 and narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxaflangedventrallyresultinginasharpcarina.Gut not studied. Soldier C olour . Head capsule uniformly C5. Antennae and labrum one to two palette levels paler than head capsule. Mandibles dark (C6) with an abrupt clearing on their bases (one levels) which is generally the same colour as frons. Thorax and legs paler than head capsule (C4). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×or more). Labrum with 4–6 large setae on each lobe. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs:forecoxawithatleastonefinesetaand2–3spinesoncarina and not any spine on ventral side; trochanter generally with some strong lined-up setae, including 3–4 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 6–12 spines along their shaft. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 9, Fig. 50). Size: the soldiers of I. modicus sp. nov. are part of the smallest soldiers in the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised; appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a very slight narrowing near posterior third or fourth; from antennal sockets sides converge towards bases of mandibles; posterior side regularly convex. Slightly concave or straight upper profile; angle between extended mandibles and fronsobtuse;fronsflatorwithasmallanteriorhump.Gulamentuminventralviewalwaysconstricted in its posterior half, with sides of anterior part roundly convex. Antennae: of 14.5–15 articles. Labrum: alwaysdeeplybifurcateandwiderthanlong,withlyre-shapedsides;lobesangular,withfine,whitish,or translucent tips; anterior margin concave. Mandibles: sabre-like; inner edges smooth with one distinct but small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible slightly more curved than left. Thorax: pronotum sellate, as wide as 56–60% of head width, with straight anterior and posterior margins. Fore coxaflangedventrallyresultinginasharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Caecum rather small, best seen in ventral view, near centre of abdomen, three-lobed. Arrangement of enteric valve cushions showing trilateral symmetry, the odd cushions recognizable as a finitimus EVA. Worker Colour. Head capsule pale (C2–C3). Antennae: proximal articles pale (C2), distal articles two levels darker (C4). Thorax, nota, and legs pale (C2–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxacarinated,bearingonefinesetaandfurnished with 3–5 spines on carina and not any one on ventral side; fore trochanter with 4–6 lined up spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of 6–12 spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 99 StruCture (measurements in Table 9, Fig. 50). Size: the workers of I. modicus sp. nov. are the smallest workers with a finitimus EVA, of the same size as the smallest workers of I. fungifaber (which have a fungifaber EVA). Head capsule: weakly sclerotised (except mandibles). Antennae: 14.5 articles. Labrum: cupola shaped. Left mandible: apical tooth well developed with a sharp tip when fresh; marginal teeth threeinnumber,firstmarginalwelldevelopedbutwithablunttipevenwhenfresh,secondmarginal faint (visible as an undulated edge and disappearing in worn mandibles), third marginal with a blunt tip; premolar tooth with its proximal end generally hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apicaltoothwelldevelopedwithasharptipwhenfresh;marginalteethtwoinnumber;firstmarginalwell developed with a sharp tip when fresh; second marginal smaller and with a blunt tip even when fresh; molartoothbearingaventralroundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum sellate, as wide as about 64% of head width. Fore coxaflangedventrallyresultinginasharpcarina. Gut: enteric valve seating on left side, best seen in ventral view, situated in posterior half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, are wide and bear at that place a high density of rather short bristles on a globular bulge (Fig. 50); supporting bristles are rather numerous: 20–28 on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre of abdomen, shortly lobed (three or four small lobes). Chorology-ecology To date, this species is only known only from the “Forêt des Abeilles”, Gabon, at the limit of the northwestern Congolian lowland forests and the Atlantic equatorial coastal forest ecoregions (Fig. 53). Molecular data No genetic sequence is currently available. Isognathotermes phallicaecalis Josens & Deligne sp. nov. urn:lsid:zoobank.org:act:0647CCCF-BF5A-4FEA-9C01-84FF782A06D9 Figs 26–31, 33, 51–52, distribution map: Fig. 53; Table 10 Diagnosis Soldiers and workers of Isognathotermes phallicaecalis sp. nov. and I. phalloides sp. nov. share the samekindofphalloidcecum,extendedforwardinafinger-likeprocessthatcanbeswollendistallyor capped or crowned (Figs 52, 56), which distinguishes them from all other species of Isognathotermes; they have morphologically similar soldiers, with a slight difference in the curvature of the mandibles (Fig. 22); however, they come from different ecosystems: continental evergreen forest in the case of I. phallicaecalis, forest galleries in the case of I. phalloides. The worker of I. phallicaecalis sp. nov. has a finitimus EVA and is among the small workers in the genus Isognathotermes. Its head is, on average, somewhat wider than that of I. phalloides sp. nov. (Fig. 30). The soldier’s EVA can generally be recognized as belonging to the finitimus pattern; on average it has longer mandibles than I. phalloides sp. nov.: SMlL = 2.17 –2.53 mm (vs 1.99–2.36 mm in I. phalloides). The imago is unknown. Thisspeciesisalsodefinedbyitsecologyandchorology:todateithasbeenfoundonlyinforested environments of the northern Congo Republic and Cameroon (Fig. 53). European Journal of Taxonomy 1024: 1–197 (2025) 100 Etymology The epithet phallicaecalisfromtheGreekφαλλός(phallos, phallus) and the Latin caecalis (of the caecum) refers to the caecum phalloid morphology in workers and soldiers. Material examined Twelve samples from three locations. Holotype CONGOREPUBLIC•soldier;Loundoungou;2°22.827′N,17°4.226′E;4Dec.2017;Y.Roisinleg.; study code: DJ 0529; GenBank nos MN646722 (COI) MN685925 (COII) MN685986 (28S) PQ679196 (mitogenome); BE RMCA INS.Iso.059288. Paratypes CONGO REPUBLIC • soldier, worker; same data as for holotype; BE RMCA INS.Iso.059936. Other material examined CAMEROON•soldier;DjaRock;3°20.73′N,12°42.84′E;30Mar.2015;J.Šobotnikleg.;studycode: DJ B320; BE RMCA INS.Iso.059287. CONGOREPUBLIC•soldier,worker;Mokabi;3°8.796′N,16°57.869′E;8Dec.2017;Y.Roisinleg.; study code: DJ 0527; GenBank no PQ679190 (mitogenome); BE RMCA INS.Iso.059290 • soldier, worker;Mokabi;3°8.795′N,16°57.826′E;8Dec.2017;Y.Roisinleg.;studycode:DJ0528;BERMCA INS.Iso.059289•soldier,worker;Loundoungou;2°22.929′N,17°4.301′E;Dec.2018;S.Lenzleg.; study code: DJ 0759; GenBank no PV564652 (mitogenome); BE RMCA INS.Iso.059296 • soldier, worker;Loundoungou;2°22.93′N,17°4.301′E;Dec.2018;S.Lenzleg.;studycode:DJ0760;GenBank noPV564657(mitogenome);BERMCAINS.Iso.059291•soldier,worker;Loundoungou;2°22.93′N, 17°4.301′E;Dec.2018;S.Lenzleg.;studycode:DJ0761;GenBanknoPQ679202(mitogenome); BERMCAINS.Iso.059297•soldier,worker;Loundoungou;2°22.93′N,17°4.301′E;Dec.2018;S. Lenzleg.;studycode:DJ0762;BERMCAINS.Iso.059292•soldier,worker;Loundoungou;2°22.93′N, 17°4.301′E;Dec.2018;S.Lenzleg.;studycode:DJ0763;BERMCAINS.Iso.059295•soldier,worker; Loundoungou;2°22.93′N,17°4.301′E;Dec.2018;S.Lenzleg.;studycode:DJ0764;BERMCAINS. Iso.059293•soldier,worker;Loundoungou;2°22.93′N,17°4.301′E;Dec.2018;S.Lenzleg.;study code:DJ0765;BERMCAINS.Iso.059298•soldier,worker;Loundoungou;2°22.93′N,17°4.301′E; Dec. 2018; S. Lenz leg.; study code: DJ 0766; GenBank no PV564655 (mitogenome); BE RMCA INS. Iso.059294. Historical review This species is described here; the imago is still unknown. It was recently discovered by three of us (JŠ, YR & SL) in Cameroon and Northern Congo. Description Imago The imago is unknown. Soldier C olour . Head capsule tending towards faded palette (Cf4–Cf5); there is a gradient from a darker frons to a paler back. Antennae and labrum concolorous with or somewhat paler than frons. Mandibles dark (C7–C8) with an abrupt clearing on their bases (C5–C6) which is concolorous with frons. Thorax and legs generally paler (C3–C4) than head capsule. Abdomen grey to red-brown owing to digestive bolus, sometimes with a yellowish tinge on tergites. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 101 Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Labrum always with 3–6 large setae on each lobe. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs: fore coxa bear 1–3 spines on carina and none (rarely one) on ventral side; trochanter with 2–8 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of 8–15 spines along their shaft. Abdomen: tergites with some large setae, mainly on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 10; Figs 51–52). Size: the soldiers of I. phallicaecalis sp. nov. are medium sized among of the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised, appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a clear narrowing near posterior fourth (Fig. 51), from antennal sockets sides converge more or less clearly towards bases of mandibles; posterior side regularly rounded or with a short straight middle part; upper profile concave. Angle between extended mandibles and frons a little obtuse; frons without any or with a week anterior hump. Gulamentum in ventral view always constricted in its posterior half, with sides of anterior part forming an acute widening or a kind of ear on each side. Antennae: of 14.5–15 articles. Labrum: alwaysdeeplybifurcateandwiderthanlong,withlyre-shapedsides;lobesangular,withfine,translucent tips; anterior margin concave. Mandibles: sabre-like with a middle-sized curvature in the genus Isognathotermes; inner edges generally smooth with one distinct but very small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and Fig. 51. Isognathotermes phallicaecalis Josens & Deligne sp. nov.: soldier, and worker. A. Lateral and dorsal views of the head capsule, ventral view of mandibles, and dorsal view of labrum of a soldier from the I. phallicaecalis type colony (DJ 0529). B. PC1s of soldier’s and worker’s enteric valves; caecum, and foreleg of this worker. European Journal of Taxonomy 1024: 1–197 (2025) 102 Table 10. Isognathotermes phallicaecalis Josens&Delignesp.nov.:rangesofsignificantmeasuresin soldiers and workers (imagines are unknown), in alphabetical orders of “Code” column. Variable *Code *Range Type Soldiers (n = 12) Raw measures (mm) Head: upper sagitta SHdC 0.02–0.07 0.06 Head: length SHdL 2.71–3.12 3.11 Head: width SHdW 1.84–2.13 2.07 Left mandible: lesser sagitta SMlc 0.18–0.26 0.21 Left mandible: ventral length SMlL 2.17–2.53 2.40 Hind tibia: length ST3L 1.52–1.69 1.64 Indices Head elongation index SHdL/SHdW 1.35–1.57 1.50 Left mandible: apical curvature index SMlc/SMlL 0.08–0.11 0.09 Mandibles: curvature symmetry SMlc/SMrc 0.76–1.01 0.92 Workers (n = 11) Raw measures (mm) Head: width WHdW 1.15–1.26 1.21 Left mandible: A-m1 distance WMlAmD 0.16–0.20 0.18 Left mandible: total length WMlL 0.54–0.59 0.57 Hind tibia: length WT3L 1.22–1.37 1.31 Valve: PC average length WVP-AvL 0.53–0.61 0.60 Valve: PC average width WVP-AvW 0.06–0.08 0.08 Valve: SC average length WVS-AvL 0.42–0.47 0.43 Valve: SC average width WVS-AvW 0.19–0.24 0.23 Index Valve: odd PC elongation index WVPOdd-Elg 6.76–10.2 8.27 *Abbreviations:seedefinitionsinMaterialandmethods. Fig. 52. Isognathotermes phallicaecalis Josens & Deligne sp. nov. and I. phalloides Josens & Deligne sp.nov.Diversityofphalloidcaecummorphologyinsoldiersandworkersfromfivedifferentcolonies. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 103 glossy. Right mandible slightly more curved than left. Thorax: pronotum sellate, as wide as 59–64% of head width, with generally entire anterior and posterior margins. Fore coxaflangedventrallyresulting in a more or less sharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Caecum always rather well developed, best seen in ventral view, near centre ofabdomen,asatypicalfinger-likeprocess,extendedforwardandgenerallyswollendistallyorseeming to be capped (Figs 52, 56). Arrangement of enteric valve cushions showing trilateral symmetry, the odd cushions being 20–25% longer than the even cushions, with a pilosity becoming very dense distally showing the place where a hump would be expected (in comparison with the worker’s EVA). Worker Colour. Head capsule pale (C2–C3). Antennae: proximal articles pale (C2), distal articles two levels darker (C4). Thorax, nota, and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxacarinated,bearingonefinesetaandfurnished with 3–6 spines on carina and 1–2 on ventral side; fore trochanter with 5–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of 6–15 spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 10; Figs 51–52). Size: the workers of I. phallicaecalis sp. nov. are, on average, medium sized among the genus Isognathotermes (Fig. 30). Head capsule: weakly sclerotised (except mandibles). Antennae of 14.5 (rarely 14) articles. Labrum: cupola shaped. Left mandible: apical toothwelldevelopedwithasharptipwhenfresh;marginalteeththreeinnumber,firstmarginaltooth well developed but with a blunt tip even when fresh, second marginal tooth faint (visible as an undulated edge and disappearing in worn mandibles), third marginal tooth with a blunt tip; premolar tooth with its proximal end not hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed withasharptipwhenfresh;marginalteethtwoinnumber;firstmarginaltoothwelldevelopedwitha sharp tip when fresh; second marginal tooth smaller and with a blunt tip even when fresh; molar tooth bearingaventralroundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum sellate, as wide as 66–71% of head width. Fore coxaflangedventrallyresultinginasharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern (Fig. 5) with triradial symmetry: the odd PCs, in their downstream part, bear a higher density of rather short bristles on a globular bulge, the latter sometimes weakly developed; supporting bristles are numerous: 18–33 on each side of the odd PCs (Fig. 51); secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always well developed, best seen in ventral view, near centre of abdomen, as a finger-likeprocess,extendedforwardandoftenswollendistallyorseemingtobecapped(Figs52,56). Chorology-ecology To date, this species is only known from two sites in the northern Congo Republic and one in Cameroon (in the northwestern Congolian lowland forest ecoregion: Fig. 53). Molecular data This species was previously published under the label “pha2” (DJ 0529), established as sister to I. planifrons (Hellemans et al. 2021). Six mitogenomes of I. phallicaecalis sp. nov. are published alongside this work (GenBank accessions: see Supp.file3 and ‘Material examined’). The mitogenomes European Journal of Taxonomy 1024: 1–197 (2025) 104 exhibit less than 1.21% dissimilarity with each other (Supp.file4); and a dissimilarity of up to 2.26% with I. phalloidessp.nov.–theothersamplesexhibitingphalloidcaeca–whichjustifiesthecreationoftwo different (new) species. Of note, I. phallicaecalis sp. nov. is paraphyletic with respect to I.similifinitimus sp. nov. (Fig. 33), to which mitogenomes are less than 1.50% dissimilar. Even though these two species were found non-monophyletic, the clear morphological and anatomical differences (e.g., caecum) support their recognition as distinct species. Our use of (maternally inherited) mitogenomes only may have limited our ability to resolve their evolutionary relationships. Thus, we posit that their respective paraphylies may either stem from incomplete lineage sorting, or mitogenome introgression following hybridization. Future analyses leveraging nuclear loci will be crucial to shed further light on their relationships. Isognathotermes phalloides Josens & Deligne sp. nov. urn:lsid:zoobank.org:act:0B43D017-1D4C-46CD-B30C-52B9226BDD36 Figs 26–31, 33, 54–56, distribution map: Fig. 53; Table 11 Diagnosis This species is close to I. phallicaecalis sp. nov.; like the latter, its soldier and worker are characterised byaphalloidcaecum,extendedforwardinafinger-likeprocessthatcanbeswollendistallyorcapped or crowned (Figs 52, 56). The imago’s caecum, without being phalloid, is also more developed than in imagines of other species and takes the appearance of a forward-pointing comma. Isognathotermes phallicaecalis sp. nov. and I. phalloides sp. nov. have morphologically similar soldiers, with a slight difference in the curvature of the mandibles (Fig. 22); however, they come from different Fig. 53. Distribution map of Isognathotermes modicus Josens & Deligne sp. nov. (blue triangles); I. phallicaecalis Josens & Deligne sp. nov. (blue dots); I. phalloides Josens & Deligne sp. nov. (red dots); I. rectimalatus Josens & Deligne sp. nov. (green dots). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 105 ecosystems: continental evergreen forest in the case of I. phallicaecalis, forest galleries in the case of I. phalloides. The worker has a finitimus EVA and is among the smallest workers in the genus Isognathotermes; its head is, on average, narrower than that of I. phallicaecalis sp. nov. (Fig. 30). The soldier can be distinguished from I. phallicaecalis sp. nov. by its shorter mandibles, SMlL = 1.99–2.36 mm (vs SMlL = 2.17–2.53 mm in I. phallicaecalis); its EVA can generally be recognized as belonging to the finitimus pattern. The imago is, on average and with I. fungifaber, the smallest in the genus Isognathotermes: IHdW = 1.38–1.54 mm (Fig. 26). Thisspeciesisalsodefinedbyitsecologyandchorology:allsamplescomefromforestgalleriessoutheast of the Congolian forests (Fig. 53). Etymology The epithet phalloidesfromtheGreekφαλλός(phallos,phallus)andεἶδος(eidos, like) refers to the caecum morphology in workers and soldiers. Material examined Fifty-two samples from 17 locations. Of the 46 old museum samples examined, six were initially labelled as C. fungifaber, three as C. fungifaber var. elongata,fiveasC. gibbifrons, and 32 as Cubitermes sp. Holotype DEMOCRATICREPUBLICOFTHECONGO•soldier;Kondué;4°58′S,23°19′E;ca1905;E.Luja leg.; study code: DJ 0087; initially C. gibbifrons in RMCA; BE RMCA INS.Iso.059341. Paratypes DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♀(alate),♂(alate);samedataasfor holotype; BE RMCA INS.Iso.059937. Other material examined ANGOLA•soldier,worker;Quimucanda;8°5.14′S,15°7.43′E;27Nov.2024;J.Šobotnikleg.;study code:DJ0971;BERMCAINS.Iso.059427•soldier,worker;Quimucanda;8°5.14′S,15°7.43′E;27 Nov. 2024; J. Šobotnik leg.; study code: DJ 0972; BE RMCA INS.Iso.059428. DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♀(alate),♂(alate);Kondué;4°58′S, 23°19′E;ca1905;E.Lujaleg.;studycode:DJ0088;initiallyC. gibbifrons in RMCA; BE RMCA INS.Iso.059342•worker;Kondué;4°58′S,23°19′E;ca1905;E.Lujaleg.;studycode:DJ0089; initially C. gibbifronsinRMCA;BERMCAINS.Iso.059343•soldier,worker,♀(alate),♂(alate); Kondué;4°58′S,23°19′E;ca1905;E.Lujaleg.;studycode:DJ0090;initiallyC. gibbifrons in RMCA; BERMCAINS.Iso.059344•soldier,worker,♀(queen);Kondué;4°58′S,23°19′E;1905;E.Lujaleg.; study code: DJ 0095; initially Eutermes fungifaber in RMCA; BE RMCA INS.Iso.059338 • worker, ♂(alate);Kondué;4°58′S,23°19′E;ca1905;E.Lujaleg.;studycode:DJ0098;initiallyC. fungifaber var. elongatainRMCA;BERMCAINS.Iso.059339•worker,♀(alate),♂(alate);;4°58′S,23°19′E; ca 1905; E. Luja leg.; study code: DJ 0099; initially C. fungifaber var. elongata in RMCA; BE RMCA INS.Iso.059340•worker,♂(alate);Kondué(?);4°58′S,23°19′E;ca1905;E.Lujaleg.;studycode: DJ 0606; initially C. gibbifrons;IEAP•soldier,worker,♀(alate);Bandundu;3°19′S,17°20′E;28Aug. 1939; J. Ruelle leg.; study code: DJ 0879; initially C. fungifaber var. elongata in RMCA; BE RMCA European Journal of Taxonomy 1024: 1–197 (2025) 112 Antennae of 14–14.5 articles. Labrum: cupola shaped. Left mandible: apical tooth well developed with asharptipwhenfresh;marginalteeththreeinnumber,firstmarginaltoothwelldevelopedbutwitha blunt tip even when fresh, second marginal tooth faint (visible as an undulated edge and disappearing in worn mandibles), third marginal tooth with a blunt tip; premolar tooth with its proximal end partly hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed with a sharp tip whenfresh;marginalteethtwoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhen fresh; second marginal tooth smaller and with a blunt tip even when fresh; molar tooth bearing a ventral roundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum sellate, as wide as 66–73% of head width. Fore coxaflangedventrallyresultinginasharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, bear a higher density of rather short bristles on a globular bulge (finitimus EVA, Fig. 5); supporting bristles are numerous: 19–32 on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather well developed,bestseeninventralview,nearcentreofabdomen,asatypicalfinger-likeprocess,extended forward and sometimes swollen distally or seeming to be capped (Fig. 56). Chorology-ecology This species is linked with the forest galleries of the south-western Congolian forest savanna mosaic ecoregion (Fig. 53). Molecular data Herein, one mitogenome of I. phalloides sp. nov. is published alongside this work (GenBank accession: see Supp.file3 and ‘Material examined’). The representative of I. phalloides sp. nov. exhibited a dissimilarity of up to 2.26% with samples of I. phallicaecalis sp. nov. – the other species exhibiting a phalloid caecum –, and up to 2.43% with samples of I.similifinitimus sp. nov. (see Supp.file4). This sample was previously published under the label “phal” (DJ 0459), inserted within the species I. severus based on a phylogeny reconstructed from the COII gene (Hellemans et al. 2021). Herein, the same sample was re-sequenced for its mitogenome. The phylogeny based on COII extracted from mitogenomes again placed this sample within the species I. severus (Supp.file2). However, the phylogenetic reconstruction from full mitogenomes places this species as sister to a clade containing finitimus+minitabundus+ugandensis+severus (Fig. 33), with low support values (SH-aLRT = 70.7; UFB = 82). Further analyses leveraging more samples and nuclear loci will be required to better ascertain its phylogenetic position. Isognathotermes planifrons (Sjöstedt, 1924) Figs 26–31, 33, 57–59, distribution map: Fig. 47; Table 12 Cubitermes planifrons Sjöstedt, 1924b: 255–256. Cubitermes fungifaber var. elongata Sjöstedt, 1924b: 256. Syn. nov. Cubitermes loubetsiensis Sjöstedt, 1924c: 493. Syn. nov. Mirotermes (Cubitermes) gaigeiEmerson,1928:516–517,fig.59.Syn. nov. Mirotermes (Cubitermes) loubetsiensis–Emerson1928:515–516,text-fig.58,plXXX. Cubitermes planifrons – Sjöstedt 1926: 243–244. — Snyder 1949: 162. — Ruelle 1992: 500. — Krishna et al. 2013: 1931. — Josens & Deligne 2019: 60–61. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 113 Cubitermes sp. affinis subarquatus “spB” – Roy et al. 2006: 4–5. Isognathotermes planifrons – Hellemans et al. 2021: 233. Diagnosis ThisspeciesisdifficulttoidentifyfromitsmorphologysinceitislocatednearI.finitimus and I. phalloides sp. nov. It is obviously easier to identify from its COII sequence: I. planifrons makes a clade well apart from the finitimus clade (Hellemans et al. 2021: 231). Best recognition, if molecular data are not available, by a combination of worker’s EVA, soldier’s mandibles curvature, and geographic origin. The worker has a finitimus EVA (Fig. 5) and is among the medium-sized workers of the genus Isognathotermes (Fig. 30) but with a rather small-sized enteric valve (Fig. 31). The soldier has, on average and along with that of I. fungifaber, the highest left mandible apical curvature index; it is among the medium-sized soldiers of Isognathotermes (Fig. 28); on the odd PCs of its enteric valve, the pilosity becomes very dense showing the place where a bulge exists in the worker’s valve, its finitimus pattern is therefore recognizable. The imago is, on average, medium sized in the genus Isognathotermes (Fig. 26) with, on average, larger eyes and ocelli than I.finitimus. Thisspeciesisalsodefinedbyitsecologyandchorology:ithasalwaysbeenfoundinevergreenforests from Gabon to CAR, up to 1000 km from the Atlantic coast (Fig. 47). Some samples of I. planifrons are like I. fungifaber, but they have different EVAs. Some samples of I. planifrons are like I. phalloides sp. nov.; (Fig. 22) they have similar EVAs, but they have different caeca and geographical distributions. Many samples of I. planifrons are like I.finitimus, (Fig. 22) they have similar EVAs and caeca; but their geographical distributions are different, but in CAR (Figs 38, 47). Etymology The epithet planifrons from the Latin planus(flat)andfrons (forehead) refers to the soldier’s head morphology (not protruding frons). Material examined Seventy-seven samples from 29 locations. Of the 41 old museum samples examined, only one, the type, wasidentifiedasC. planifrons (and subsequently renamed “C. fungifaber”); six samples were labelled as C. banksi, two as C. bulbifrons, one as C.finitimus, three as C. fungifaber, one as C. fungifaber var. elongata, six as C. gaigei, one as C. loubetsiensis, one as C. subarquatus, six as Cubitermes sp. and 13 notidentified. This species also includes C. aff. subarquatus “spB” (in Roy et al. 2006). Syntypes of Cubitermes planifrons Sjöstedt, 1924 DEMOCRATICREPUBLICOFTHECONGO•soldier,worker;Mukimbungu;5°8.5′S,14°2.3′E; 25 Oct. 1904; K.E. Laman leg.; study code: DJ 0296; initially C. planifrons→C. fungifaber; AMNH. Krishna et al. (2013: 1931) report imagines in the AMNH syntype but the sample that was examined did not contain any. They also mention that another syntype subsample is deposited in NHRM, not examined. European Journal of Taxonomy 1024: 1–197 (2025) 114 Paratypes from type colony of Cubitermes fungifaber var. elongata Sjöstedt, 1924 DEMOCRATICREPUBLICOFTHECONGO•soldier,worker;Mukimbungu;5°8.5′S,14°2.3′E;ca 1904; K.E. Laman leg.; study code: DJ 0270; initially C. fungifaber var. elongata; AMNH Krishna et al. (2013: 1931) mention that another syntype subsample is deposited in NHRM (not examined). Paratypes of Mirotermes (Cubitermes) gaigei Emerson, 1928 CAMEROON•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G.Zenkerleg.;studycode:DJ0274; initially C. gaigei→C. fungifaber;AMNH•soldier,worker;Bipindi;3°5′N,10°24.5′E;1920;G. Zenker leg.; study code: DJ 0288; initially C. gaigei→C. fungifaber; AMNH. Paratypes of Cubitermes loubetsiensis Sjöstedt, 1924 CONGOREPUBLIC•soldier;Loubetsi;3°12′S,12°10′E;1924;Nilssonleg.;studycode:DJ0611; initially C. loubetsiensis→Cfinitimus;AMNH•soldier;Loubetsi;3°12′S,12°10′E;[nodate];Kranz leg.; study code: DJ 0281; initially C. loubetsiensis; NHMM. Other material examined ANGOLA•soldier,worker,♀(alate);Quimucanda;8°5.14′S,15°7.43′E;28Nov.2024;J.Šobotnik leg.; study code: DJ 0973; BE_RMCA_INS.Iso.059898. CAMEROON•soldier,worker;Bipindi;3°5′N,10°24.5′E;1903;G.Zenkerleg.;studycode:DJ0961; initially Eutermes zenkeri;RBINS•soldier,worker,♀(queen);Bipindi;3°5′N,10°24.5′E;1920;G. Zenker leg.; study code: DJ 0276; initially C. fungifaber; AMNH • soldier; 45 km from Abong-Mbang; 5°16′N,17°38′E;1Jul.1948;P.-P.GrasséandC.Noirotleg.;studycode:DJP195;MNHNEP9900• soldier,worker,♂(alate);RéserveforestièredeNyong;3°33′N,11°37′E;5Dec.1949;J.BirkettSmith and J. Dahl leg.; study code: DJ 0678; initially C. subarquatus; NHMUK 13671991 • soldier; Eboufek;3°30′N,11°53′E;1Dec.1962;G.Beckerleg.;studycode:DJU066;initiallyC. banksi; NHMUK13671829•soldier;Akok;3°53′N,11°57′E;ca1995;P.Eggletonet al. leg.; study code: DJ U096; initially C. bulbifrons;NHMUK13671844•soldier;Akok;3°53′N,11°57′E;ca1995; P. Eggleton et al. leg.; study code: DJ U097; initially C. bulbifrons; NHMUK 13671841 • soldier; Bilik;3°31′N,11°17′E;ca1995;P.Eggletonet al. leg.; study code: DJ U067; initially C. banksi; NHMUK13671832•soldier,♂(king);Bilik;3°31′N,11°17′E;ca1995;P.Eggletonet al. leg.; study code: DJ U091; initially C. banksi;NHMUK13671827•soldier,worker;Bilik;3°31′N,11°17′E;ca 1995; P. Eggleton et al. leg.; study code: DJ 0705; initially C. banksi; NHMUK 13671830 • soldier; Ebogo;3°31′N,11°30′E;ca1995;P.Eggletonet al. leg.; study code: DJ U093; initially C. banksi; NHMUK13671833•soldier;Ebogo;3°31′N,11°30′E;ca1995;P.Eggletonet al. leg.; study code: DJ U119; initially C. gaigei;NHMUK13671904•soldier,worker;Ebogo;3°23′N,11°28′E;ca 1995; P. Eggleton et al. leg.; study code: DJ 0703; initially C. banksi; NHMUK 13671834 • soldier; Mbalmayo;3°28′N,11°31′E;ca1995;P.Eggletonet al. leg.; study code: DJ U118; initially C. gaigei; NHMUK13671903•♀(queen);Mbalmayo;3°31′N,11°30′E;ca1995;P.Eggletonet al. leg.; study code: DJ 0724; initially C. gaigei;NHMUK•soldier,worker;Nsimi;3°10′N,11°58′E;Nov.1996; M. Harry leg.; study code: DJ 0754; GenBank no PQ679239 (mitogenome); MNHN EP9901 • soldier, worker;Nsimi;3°10′N,11°58′E;Nov.1996;M.Harryleg.;studycode:DJ0755;GenBankno PQ679178(mitogenome);MNHNEP9902•soldier;Djaforest;3°20.63′N,12°43.03′E;30Mar.2015; J.Šobotnikleg.;studycode:DJB321;BERMCAINS.Iso.059347•soldier;DjaRock;3°20.73′N, 12°42.84′E;30Mar.2015;J.Šobotnikleg.;studycode:DJB319;BERMCAINS.Iso.059348•soldier, worker;nearSomalomo;3°20.7′N,12°42.8′E;30Mar.2015;J.Šobotnikleg.;studycode:DJ0259; BERMCAINS.Iso.059356•soldier,worker;Ebogo;3°22.95′N,11°27.718′E;22May2017;Y. Roisinleg.;studycode:DJ0509;BERMCAINS.Iso.059361•soldier,worker;Ebogo;3°22.772′N, JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 115 11°27.899′E;24May2017;Y.Roisinleg.;studycode:DJ0518;BERMCAINS.Iso.059362•soldier, worker,♂(king);Ebogo;3°22.914′N,11°27.8′E;26May2017;Y.Roisinleg.;studycode:DJ0519; GenBank no PQ679176 (mitogenome); BE RMCA INS.Iso.059363 • soldier, worker; Yolo-Chimpa; 5°35.136′N,10°53.301′E;30May2017;Y.Roisinleg.;studycode:DJ0508;GenBanknosMN646726 (COI), MN685929 (COII), MN685990 (28S); BE RMCA INS.Iso.059364 • soldier, worker; Akometa; 3°28.194′N,11°32.814′E;6Jun.2017;Y.Roisinleg.;studycode:DJ0507;GenBanknosMN646725 (COI), MN685928 (COII), MN685989 (28S), PQ679210 (mitogenome); BE RMCA INS.Iso.059365 • soldier,worker,♂(king),♀(queen);Ebogo;3°22.935′N,11°27.793′E;7Jun.2017;Y.Roisinleg.; studycode:DJ0511;BERMCAINS.Iso.059366•soldier,worker;Nguinda;4°15′N,12°11′E;23Nov. 2023; J. Šobotnik leg.; study code: DJ 0954; GenBank no PV564654 (mitogenome); BE RMCA INS. Iso.059489•soldier,worker;Nguinda;4°15′N,12°11′E;25Nov.2023;J.Šobotnikleg.;studycode: DJ 0951; GenBank no PV564644 (mitogenome); BE RMCA INS.Iso.059372 • soldier, worker; Nguinda; 4°15′N,12°11′E;25Nov.2023;J.Šobotnikleg.;studycode:DJ0953;GenBanknoPV564645 (mitogenome);BERMCAINS.Iso.059488•soldier,worker;Nguinda;4°15′N,12°11′E;3Dec.2023;J. Šobotnik leg.; study code: DJ 0950; GenBank no PV564653 (mitogenome); BE RMCA INS.Iso.059373 • soldier;Nguinda;4°15′N,12°11′E;3Dec.2023;J.Šobotnikleg.;studycode:DJ0957;GenBankno PV564659 (mitogenome); BE RMCA INS.Iso.059155. CENTRALAFRICANREPUBLIC•soldier;Boukoko;3°54′N,17°55′E;21Jun.1948;P.-P.Grassé andC.Noirotleg.;studycode:DJP185;MNHNEP9898•soldier;Boukoko;3°54′N,17°55′E;21 Jun. 1948; P.-P. Grassé and C. Noirot leg.; study code: DJ P186; MNHN EP9899 • soldier, worker, ♀(alate);Bounguélé;3°57′N,16°45′E;12May2007;N.Sionleg.;studycode:DJ0931;BERMCA INS.Iso.059355. CONGOREPUBLIC•soldier;Ouesso;1°37′N,16°1′E;27Dec.1956;P.-P.GrasséandC.Noirot leg.;studycode:DJP168;MNHNEP9896•soldier,worker;Dimonika;4°12′S,12°20′E;21Apr. 1983;C.Noirotleg.;studycode:DJ0930;MNHNEP9894•soldier,worker,♀(queen);Loundoungou; 2°22.973′N,17°4.298′E;3Dec.2017;Y.Roisinleg.;studycode:DJ0526;GenBanknosMN646728 (COI), MN685931 (COII), MN685992 (28S); BE RMCA INS.Iso.059357 • soldier, worker; Loundoungou;2°22.929′N,17°4.301′E;4Dec.2017;Y.Roisinleg.;studycode:DJ0524;GenBank noPQ679227(mitogenome);BERMCAINS.Iso.059358•soldier,worker;Mokabi;3°8.795′N, 16°57.826′E;6Dec.2017;Y.Roisinleg.;studycode:DJ0523;GenBanknosMN646727(COI), MN685930 (COII), MN685991 (28S);BERMCAINS.Iso.059359•soldier,worker;Mokabi;3°9.022′N, 16°58.214′E;8Dec.2017;Y.Roisinleg.;studycode:DJ0525;GenBanknoPQ679194(mitogenome); BERMCAINS.Iso.059360•soldier,worker;Loundoungou;2°22.93′N,17°4.301′E;Dec.2018;S. Lenz leg.; study code: DJ 0767; GenBank no PV564648 (mitogenome); BE RMCA INS.Iso.059371. DEMOCRATICREPUBLICOFTHECONGO•soldier;Mekambo;1°1′N,13°56′E;8Jan.1957;P.- P.GrasséandC.Noirotleg.;studycode:DJP171;MNHNEP9897•soldier;ForêtdeDjidji;0°13′N, 11°48′E;26Jan.1957;P.-P.GrasséandC.Noirotleg.;studycode:DJP162;GenBanknoPQ679182 (mitogenome);MNHNEP9895•soldier;RouteMakokou-Mekambo;0°41′N,13°2′E;6Jun.1962;J. Deligne leg.; study code: DJ U099; initially C. gaigei; NHMUK 13671888 • soldier; Forêt des Abeilles; 0°19′S,12°7′E;1995;C.Bordereau(?)leg.;studycode:DJP218;MNHNEP9891•soldier;Forêtdes Abeilles;0°19′S,12°7′E;1995;C.Bordereau(?)leg.;studycode:DJP219;MNHNEP9892•soldier; ForêtdesAbeilles;0°19′S,12°7′E;1995;C.Bordereau(?)leg.;studycode:DJP221;MNHNEP9893• soldier,worker;ForêtdesAbeilles;0°35′S,12°25′E;1995;C.BordereauandA.Robertleg.;studycode: DJ0861;MNHNEP9889•soldier,worker;ForêtdesAbeilles;0°19′S,12°7′E;1995;C.Bordereau andA.Robertleg.;studycode:DJ0863;MNHNEP9890•soldier;LaLopéN.P.;0°15′S,11°35′E; 6Mar.1998;M.Harryleg.;studycode:DJP236;MNHNEP9910•soldier;LaLopéN.P.;0°9′S, 11°36′E;7Mar.1998;M.Harryleg.;studycode:DJP227;MNHNEP9904•soldier;LaLopéN.P.; European Journal of Taxonomy 1024: 1–197 (2025) 116 0°15′S,11°35′E;7Mar.1998;M.Harryleg.;studycode:DJP247;MNHNEP9915•worker;LaLopé N.P.;0°12.7′S,11°33.5′E;7Mar.1998;M.Harryleg.;studycode:DJ0632;GenBanknosDQ246542 (COII), DQ246524 (ITS2), PQ679220 (mitogenome); initially C. aff. subarquatus “spB” (cf. Roy et al. 2006);MNHNEP9919•soldier;LaLopéN.P.;0°9′S,11°36′E;9Mar.1998;M.Harryleg.;studycode: DJP229;MNHNEP9905•soldier,worker;LaLopéN.P.;0°15′S,11°35′E;9Mar.1998;M.Harryleg.; study code: DJ 0624; GenBank nos DQ127312 (COII), DQ246520 (ITS2), PQ679183 (mitogenome); initially C. aff. subarquatus “spB” (cf. Roy et al. 2006); MNHN EP9918 • soldier, worker; Doda (north ofLaLopéN.P.);0°4.5′S,11°25.5′E;10Mar.1998;M.Harryleg.;studycode:DJ0923;MNHN EP9903•soldier;LaLopéN.P.;0°12′S,11°33′E;11Mar.1998;M.Harryleg.;studycode:DJP233; MNHNEP9908•soldier;LaLopéN.P.;0°12′S,11°33′E;11Mar.1998;M.Harryleg.;studycode: DJP234;MNHNEP9909•soldier;LaLopéN.P.;0°15′S,11°35′E;11Mar.1998;M.Harryleg.;study code:DJP248;MNHNEP9916•soldier;LaLopéN.P.;0°9′S,11°41′E;15Mar.1998;M.Harryleg.; studycode:DJP230;MNJNEP9906•soldier;LaLopéN.P.;0°9′S,11°41′E;15Mar.1998;M.Harry leg.;studycode:DJP231;MNHNEP9907•soldier,♀(queen);LaLopéN.P.;0°15′S,11°35′E;15Mar. 1998;M.Harryleg.;studycode:DJP245;MNHNEP9914•worker,♂(king);LaLopéN.P.;0°15′S, 11°35′E;15Mar.1998;M.Harryleg.;studycode:DJP250;MNHNEP9917•soldier,♀(queen);La LopéN.P.;0°15′S,11°35′E;16Mar.1998;M.Harryleg.;studycode:DJP238;MNHNEP9912• soldier;LaLopéN.P.;0°15′S,11°35′E;16Mar.1998;M.Harryleg.;studycode:DJP240;MNHN EP9913•soldier;LaLopéN.P.;0°15′S,11°35′E;23Mar.1998;M.Harryleg.;studycode:DJP237; MNHNEP9911•soldier,worker;Nkobissimo[=Nkolmengboua?];2°14.3′N,11°29.25′E;15Apr. 2017; G. Trembleau leg.; study code: DJ 0455; GenBank nos MN646724 (COI), MN685927 (COII), MN685988 (28S); BE RMCA INS.Iso.059354. Historical review Sjöstedt(1924b:255–256)brieflydescribedthesoldierofthisspeciesunderthenameCubitermes planifrons. Two years later, Sjöstedt (1926: 243–244) provided more detailed descriptions of all three castes, housing the species in the sub-family Termitinae. He included (1926: 218–226) C. planifrons in imagines’ and soldiers’ keys of Cubitermes species and inserted it in a “fungifaber-Gruppe” of species with a not protruding soldier’s frons. Snyder (1949: 162) catalogued this species under the name Cubitermes planifrons and housed it in the sub-family Termitinae. This is one of the species that Ruelle (1992: 500) called “forgotten species”. Krishna et al. (2013: 1931) housed Cubitermes planifrons in the sub-family Cubitermitinae. Following Emerson’s “card catalog”, they mentioned that this species might become a junior synonym of C. fungifaber; however, this synonymy could not be accepted because C. planifrons and C. fungifaber belong to different valve pattern groups: Josens & Deligne (2019: 42–44) placed this species within the finitimus valve pattern group. Hellemans et al. (2021: 233) placed this species in the restored genus Isognathotermes. Cubitermes aff. subarquatus “spB” was mentioned by Roy et al. (2006) in La Lopé National Parc, Gabon. On a genetical base, it was considered a cryptic species. Hellemans et al. (2021: 233) placed this species in the restored genus Isognathotermes as synonym of I. planifrons. Redescription Imago Colour. Head capsule: well sclerotised, fresh samples very dark, C7–C8 (C6–C7 in long preserved imagines); fontanelle concolorous with or slightly paler than head capsule. Postclypeus C6–C7 slightly JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 117 paler (one level) than head capsule. Antennae C5–C6 without any difference between proximal and distal articles. Thorax: pronotum C6–C7 as postclypeus, generally one level paler than head capsule; mesoand metanotum C5–C6, concolorous with or somewhat paler than pronotum. Legs C3–C5; tibia usually slightly (one level) darker than femur. Wings hyaline with brown to grey tinge (Cf3–Cf4), anterior veins darker. Abdomen: tergites C6–C7. Sternites appreciably paler in middle (C2–C5) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat20–40×.Legs verypilose,furnished(amongnumerousfinesetae)withsomestrongersetae:6–10onthecarinaoffore coxa and 1–4 on the ventral side of fore coxa and sometimes also some on trochanter; tibia pilose fore, mid, and hind tibia furnished with 15–30 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 12; Figs 26–27, 57). Size: the imagines of I. planifrons are, on average, among the medium-sized of the genus Isognathotermes (Fig. 26). Head capsule: compound eyes nearly round; ocelli nearly round to oval, removed from eyes by a distance about equal to 0.7– 1.2 ocellus small diameter; fontanelle generally a tiny round marking. Antennae: 16 articles on alate individuals, always shortened by amputation in queens and kings. Labrum: cupola shaped. Left mandible with apical tooth on average rather small in comparison with other species of the genus (Fig. 27) and alwaysmoreprominentthanfirstmarginal;marginalteeththreeinnumberbutsecondoneonlysuggested byanundulationofedgebetweenfirstandthirdmarginalteeth;onlytheapicaltoothisacuteinunworn specimens; premolar tooth with proximal end obscured or partly obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandiblewithapicaltoothalwaysmoreprominentthanfirstmarginal;marginalteeth twoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhenfresh;secondmarginaltooth smallerandwithablunttipevenwhenfresh;molartoothbearingaventralroundedflangeandending posteriorly in a kind of heel. Thorax: pronotum appreciably wider than long and narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxaflangedventrallyresultinginamoreorlesssharpcarina.Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 3–4 and 10–11 branches respectively. Gut: enteric valve not studied. Fig. 57. Isognathotermes planifrons (Sjöstedt, 1924): imago. A. Lateral and dorsal views of the head capsule of the king from a non-type colony of I. planifrons (DJ 0511), and dorsal view of this imago’s mandibles. European Journal of Taxonomy 1024: 1–197 (2025) 118 Soldier Colour. Head capsule generally tending towards deep palette (Cd4–Cd5) becoming fader in long preserved samples; there is always a gradient from a darker frons to a paler back (e.g., from C5 to C4), smooth and extended in 60% of the samples examined but more abrupt in the remaining 40% giving the impression that the head capsule is bicolorous (as in Fig. 13). Antennae and labrum sometimes concolorous or one level paler than head capsule. Mandibles dark (C6–C8) generally with an abrupt clearing on their bases (two palette levels) which is generally the same colour as frons. Thorax and legs paler than head capsule (C2–C4) somewhat darker in long preserved samples. Abdomen grey to redbrown owing to digestive bolus. Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal Table 12. Isognathotermes planifrons(Sjöstedt,1924):rangesofsignificantmeasuresinthethreecastes, in alphabetical orders of the “Code” column; 77 samples from 28 locations. Variable *Code *Range Type Imagines (n = 14) Raw measures (mm) Eye: large diameter IEyD0.41–0.47 NA Head: width across the eyes IHdW 1.49–1.67 NA Left mandible: A-m1 distance IMlAmD 0.19–0.23 NA Ocellus: large diameter IOcD0.15–0.19 NA Postclypeus: width IPcW 0.72–0.81 NA Pronotum: maximal width IPnW 1.36–1.57 NA Hind tibia: length IT3L 1.30–2.00 NA Wing: length (n = 4) IWgL 13.6–14.0 NA Index Left apico-marginal index IMlAmD/IMlmmD 1.21–1.73 NA Soldiers (n = 76) Raw measures (mm) Head: upper sagitta SHdC 0.00–0.06 0.012 Head: length SHdL 2.60–3.45 3.06 Head: width SHdW 1.83–2.34 2.12 Left mandible: lesser sagitta SMlc 0.19–0.35 0.28 Left mandible: ventral length SMlL 2.13–2.62 2.40 Hind tibia: length ST3L 1.50–1.89 1.73 Indices Head elongation index SHdL/SHdW 1.35–1.63 1.44 Left mandible: apical curvature index SMlc/SMlL 0.08–0.15 0.12 Mandibles: curvature symmetry SMlc/SMrc 0.79–1.37 0.93 Workers (n = 42) Raw measures (mm) Head: width WHdW 1.08–1.30 1.21 Left mandible: A-m1 distance WMlAmD 0.16–0.20 0.18 Left mandible: total length WMlL 0.55–0.64 0.59 Hind tibia: length WT3L 1.18–1.48 1.31 Valve: PC average length WVP-AvL 0.49–0.66 0.55 Valve: PC average width WVP-AvW 0.05–0.10 0.08 Valve: SC average length WVS-AvL 0.38–0.51 0.39 Valve: SC average width WVS-AvW 0.18–0.27 0.24 Index Valve: odd PC elongation index WVPOdd-Elg 5.48–9.57 6.27 *Abbreviations:seedefinitionsinMaterialandmethods. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 119 extremityofdistalarticles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50× or more). Labrum always with some large setae on lobes. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs:forecoxabearsatleastonefinesetaandnotany spines in some (10%) samples examined but generally furnished with 1–4 spines on carina and no spines onventralside;trochantergenerallywithsomelonglined-upsetae,sometimeswithfiveorsixspines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 6–15 spines along their shaft. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 12; Figs 28, 58). Size: the soldiers of I. planifrons are medium sized in the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised; appreciably longer than wide. Dorsal view: lateral sides subparallel with a narrowing near posterior third or fourth; from antennal sockets sides converge more or less clearly towards bases of mandibles; posterior side regularly roundedor(in56%ofthesamplesexamined)withashortstraightpartinthemiddle.Upperprofile almost always slightly concave; angle between extended mandibles and frons always a little obtuse; frons generally (88%) without any anterior hump, rarely with a slight hump. Gulamentum in ventral view always constricted in its posterior half, with sides of anterior part either roundly convex or forming an acute widening or even (in 36% of the samples studied) a kind of ear on each side. Antennae: of 15 articles. Labrum: always deeply bifurcate and wider than long, with sides varying from lyre shaped (in92%ofthesamplesexamined)tostraight;lobesangular,frequentlywithfine,whitishortranslucent tips; anterior margin concave. Mandibles: sabre-like, strongly curved (on average, I. fungifaber, and I. planifrons, have the highest left mandible apical curvature index in the genus Isognathotermes); inner edges generally smooth with one distinct but generally very small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible generally slightly more curved than left. Thorax: pronotum sellate, as wide as 56–64% of head width, with generally entire anterior and posterior margins. Fore coxaflangedventrallyresulting in a more or less sharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions showing trilateral symmetry, the odd cushions being about 20% longer than the even cushions, generally without any crest or with crests very weakly developed. Caecum always rather small, best seen in ventral view, near centre of abdomen, shortly lobed. Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always one to two levels darker (C4–C5). Thorax, nota and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxacarinated,bearingonefinesetaandfurnished with 3–5 spines on carina and generally 1, rarely 2 or 3 spines on ventral side; fore trochanter with 5–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 12; Figs 30, 59). Size: the workers of I. planifrons are, on average, medium sized in the genus Isognathotermes with large overlapping on several other species (Fig. 30). European Journal of Taxonomy 1024: 1–197 (2025) 120 Head capsule: weakly sclerotised (except mandibles). Antennae of 14.5 articles. Labrum: cupola shaped. Left mandible: apical tooth well developed with a sharp tip when fresh; marginal teeth three in number, firstmarginaltoothwelldevelopedbutwithablunttipevenwhenfresh,secondmarginaltoothfaint (visible as an undulated edge and disappearing in worn mandibles), third marginal tooth with a blunt tip; premolar tooth with its proximal end generally hidden under molar prominence; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apicaltoothwelldevelopedwithasharptipwhenfresh;marginalteethtwoinnumber;firstmarginal tooth well developed with a sharp tip when fresh; second marginal tooth smaller and with a blunt tip Fig. 58. Isognathotermes planifrons (Sjöstedt, 1924) and junior synonym species: soldiers. Lateral and dorsal views of a soldier’s head capsule, ventral view of this soldier’s mandibles, and dorsal view of this soldier’s labrum. A. From the type colony of Cubitermes planifrons Sjöstedt, 1924 (DJ 0296). B. From the type colony of Cubitermes fungifaber var elongata Sjöstedt, 1924 (DJ 0270). C. From the type colony of Mirotermes (Cubitermes) gaigei Emerson, 1928 (DJ 0288). D. From the type colony of Cubitermes loubetsiensis Sjöstedt, 1924 (DJ 0611). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 121 evenwhenfresh;molartoothbearingaventralroundedflangeandendingposteriorlyinakindofheel. Thorax: pronotum sellate, as wide as 63–76% of head width. Fore coxaflangedventrallyresultingin a sharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions of the finitimus pattern with triradial symmetry: the odd PCs, in their downstream part, are wide and bear at that place a high density of rather short bristles on a globular bulge; supporting bristles are generally numerous: 17–31 on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre of abdomen, shortly lobed (generally three small lobes). Fig. 59. Isognathotermes planifrons (Sjöstedt, 1924) and junior synonym species: soldiers and workers. PC1s of a soldier’s and a worker’s enteric valves, and worker’s caecum and foreleg. A. From the type colony of Cubitermes planifrons Sjöstedt, 1924 (DJ 0296). B. From the type colony of Cubitermes fungifaber var elongata Sjöstedt, 1924 (DJ 0270). C. From the type colony of Mirotermes (Cubitermes) gaigei Emerson, 1928 (DJ 0288). European Journal of Taxonomy 1024: 1–197 (2025) 128 Syntypes of Cubitermes severus Silvestri, 1914 GUINEA•soldier,worker,♀(queen);Kakoulima;9°46′N,13°27′W;Aug.1912;F.Silvestrileg.; study code: DJ 0608; initially C. severus;IEAP•soldier,worker,♀(queen);Camayenne;9°31.83′N, 3°41.17′W;16Oct.1912;F.Silvestrileg.;studycode:DJ0609;initiallyC. severus; IEAP • soldier, worker;Kakoulima;9°46′N,13°27′W;before1904;F.Silvestrileg.;studycode:DJ0292;initially C. severus;AMNH•soldier,worker;Camayenne;9°31.8′N,13°41.5′W;16Oct.1912;F.Silvestrileg.; study code: DJ 0293; initially C. severus; AMNH Syntypes of Cubitermes severus var. modestior Silvestri, 1914 GUINEA•soldier,worker,♂(king);Kindia;10°3′N,12°52′W;20Aug.1912;F.Silvestrileg.;study code: DJ 0294; initially C. severus var. modestior;AMNH•soldier,worker,♀(queen);Kindia;10°3′N, 12°52′W;20Aug.1912;F.Silvestrileg.;studycode:DJ0341;initiallyC. severus var. modestior; IEAP. Krishna et al. (2013: 1927) mention that another subsample is deposited in PPRI (not examined). Syntypes of Cubitermes silvestrii Sjöstedt, 1925 GUINEA•soldier,worker;Kakoulima;9°46′N;13°27′W),Fr.Guinea[=Guinea];ca1912;F.Silvestri leg.; study code: DJ 0302; initially C. silvestrii; AMNH. Krishna et al. (2013: 1937) mention that another subsample is deposited in NHRM (not examined). Other material examined BENIN•soldier,worker;Birni(forêtclassée);10°1′N,1°32′E;Nov.2016;L.E.Lokoleg.;study code: DJ 0402; GenBank no PQ679191 (mitogenome); BE RMCA INS.Iso.059446 • soldier, worker, ♀(queen);Birni(forêtclassée);10°1′N,1°32′E;Nov.2016;L.E.Lokoleg.;studycode:DJ0403; GenBank nos MN646735 (COI), MN685940 (COII), MN686001 (28S); BE RMCA INS.Iso.059448 • soldier,worker;Birni(forêtclassée);10°1′N,1°32′E;Nov.2016;L.E.Lokoleg.;studycode:DJ0404; GenBank no PQ679230 (mitogenome); BE RMCA INS.Iso.059445 • soldier, worker; Birni (forêt classée);10°1′N,1°32′E;Nov.2016;L.E.Lokoleg.;studycode:DJ0405;GenBanknoPQ679200 (mitogenome);BERMCAINS.Iso.059449•soldier,worker;Birni(forêtclassée);10°1′N,1°32′E; Nov. 2016; L.E. Loko leg.; study code: DJ 0406; GenBank no PQ679221 (mitogenome); BE RMCA INS.Iso.059447. BURKINAFASO•soldier,worker;Bama;11°21′N,4°23′W;Feb.2012;S.Traoréleg.;studycode: DJ 0052; BE RMCA INS.Iso.059412. CAMEROON•soldier,worker,♂(alate);MontGuendérou;7°10′N,14°14′E;before1914?; Riggenbach leg.; study code: DJ 0324; initially C. silvestrii;AMNH•soldier,worker,♀(alate), ♂(alate);Ekoua;3°52.6′N,12°15.5′E;28Mar.2015;J.Šobotnikleg.;studycode:DJ0249;GenBank noPQ679208(mitogenome);BERMCAINS.Iso.059401•soldier,worker,♀(alate),♂(alate);Batié; 5°17′N,10°14.7′E;7Apr.2015;J.Šobotnikleg.;studycode:DJ0250;BERMCAINS.Iso.059402• soldier,worker,♀(alate),♂(alate);Koutaba;5°39.3′N,10°46.4′E;8Apr.2015;J.Šobotnikleg.; study code: DJ 0251; GenBank no PQ679250 (mitogenome); BE RMCA INS.Iso.059403 • soldier, worker;Koutaba;5°39.3′N,10°46.4′E;8Apr.2015;J.Šobotnikleg.;studycode:DJ0258;GenBank noPQ679229(mitogenome);BERMCAINS.Iso.059407•soldier,worker,♀(alate),♂(alate); Boulourou;4°48.8′N,11°0.1′E;10Apr.2015;J.Šobotnikleg.;studycode:DJ0252;BERMCAINS. Iso.059404•soldier,worker;Koutaba;5°35.988′N,10°44.973′E;31May2017;Y.Roisinleg.;study code: DJ 0530; GenBank no PQ679166 (mitogenome); BE RMCA INS.Iso.059408 • soldier, worker; Mancha;5°33.534′N,10°52.836′E;1Jun.2017;Y.Roisinleg.;studycode:DJ0510;BERMCAINS. Iso.059409•soldier,worker;Koutaba;5°35.816′N,10°45.856′E;2Jun.2017;Y.Roisinleg.;study JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 129 code: DJ 0531; GenBank no PQ679168 (mitogenome); BE RMCA INS.Iso.059410 • soldier, worker; Kimi;6°5′N,11°29′E;30Nov.2023;J.Šobotnikleg.;studycode:DJ0949;GenBanknoPV564658 (mitogenome);BERMCAINS.Iso.059405•soldier,worker;Kimi;6°5′N,11°29′E;30Nov.2023;J. Šobotnik leg.; study code: DJ 0952; GenBank no PV564651 (mitogenome); BE RMCA INS.Iso.059406. CENTRALAFRICANREPUBLIC•soldier;Bouala;6°22.8′N,15°37′E;8Jan.1914;Elbertleg.;study code: DJ U006; initially C. severus;NHMUK13671956•soldier,♀(alate);Bosoum;6°19′N,16°22′E; 1 May 1914; G. Tessmann leg.; study code: DJ U016; initially C. severus; NHMUK 13671955 • soldier; Boukoko;3°54′N,17°55′E;2Jul.1948;P.-P.GrasséandC.Noirotleg.;studycode:DJP187;MNHN EP9939•soldier;20kmNofBangui;4°37′N,18°33′E;Nov.1956;P.-P.GrasséandC.Noirotleg.; studycode:DJP174;MNHNEP9928•soldier;20kmNofBangui;4°36′N,18°31′E;Nov.1956; P.-P.GrasséandC.Noirotleg.;studycode:DJP177;MNHNEP9931•soldier;Bossembélé;5°16′N, 17°38′E;21Nov.1956;P.-P.GrasséandC.Noirotleg.;studycode:DJP175;MNHNEP9929•soldier; Bossembélé;5°16′N,17°38′E;21Nov.1956;P.-P.GrasséandC.Noirotleg.;studycode:DJP181; MNHNEP9935•soldier;70kmfromAlindao;5°30′N,20°49′E;Dec.1956;P.-P.GrasséandC.Noirot leg.;studycode:DJP180;MNHNEP9934•soldier;70kmfromAlindao;5°30′N,20°49′E;Dec. 1956;P.-P.GrasséandC.Noirotleg.;studycode:DJP184;MNHNEP9938•soldier;Bambari;5°46′N, 20°40′E;Dec.1956;P.-P.GrasséandC.Noirotleg.;studycode:DJP178;MNHNEP9932•soldier; Bambari;5°46′N,20°40′E;Dec.1956;P.-P.GrasséandC.Noirotleg.;studycode:DJP179;MNHN EP9933•soldier;Bambari;5°46′N,20°40′E;Dec.1956;P.-P.GrasséandC.Noirotleg.;studycode: DJP182;MNHNEP9936•soldier;Bambari;5°46′N,20°40′E;4Dec.1956;P.-P.GrasséandC.Noirot leg.;studycode:DJP183;MNHNEP9937•soldier;Bambari;5°46′N,20°40′E;13Dec.1956;P.-P. GrasséandC.Noirotleg.;studycode:DJP176;MNHNEP9930•soldier;Bambari;5°46′N,20°40′E; 1975; P. Eggleton et al. leg.; study code: DJ U070; initially C. ugandensis; NHMUK 13671994 • soldier;nearBangui;4°23′N,18°34.5′E;1975;Beckerleg.;studycode:DJU111;initiallyC. gaigei; NHMUK13671894•soldier,worker,♂(alate);Boika(Mbaïki);3°52′N,17°58′E;11Apr.2007;N. Sion leg.; study code: DJ 0934; GenBank no PV564656 (mitogenome); BE RMCA INS.Iso.059399 • soldier,worker;Mopiti(Mbaïki);3°52′N,17°58′E;14Apr.2007;N.Sionleg.;studycode:DJ0932; GenBank no PV564660 (mitogenome); BE RMCA INS.Iso.059418 • soldier, worker; Mopiti (Mbaïki); 3°52′N,17°58′E;14Apr.2007;N.Sionleg.;studycode:DJ0933;BERMCAINS.Iso.059417•soldier, worker;Bondoé;5°10.3′N,17°44.2′E;23Apr.2007;N.Sionleg.;studycode:DJ0004;BERMCA INS.Iso.059400•soldier,worker;Gbasabangui(Bangui);4°22.5′N,18°34.75′E;3May2007;N.Sion leg.; study code: DJ 0935; GenBank no PV564646 (mitogenome); BE RMCA INS.Iso.059452 • soldier, worker;Bondoé;5°10.3′N,17°44.2′E;27May2007;N.Sionleg.;studycode:DJ0001;BERMCA INS.Iso.059450•soldier,worker;nearBangui;4°23′N,18°34.5′E;30Oct.2010;G.Josensleg.;study code:DJ0367;BERMCAINS.Iso.059414•soldier,worker,♀(alate);Mbaïki;3°55′N,18°0′E;24 Apr.2018;S.P.Wangoleg.;studycode:DJ0586;BERMCAINS.Iso.059395•soldier,worker,♀(alate); Mbaïki;3°55′N,18°0′E;24Apr.2018;S.P.Wangoleg.;studycode:DJ0587;GenBanknoPQ679223 (mitogenome);BERMCAINS.Iso.059388•soldier,worker;Mbaïki;3°55′N,18°0′E;24Apr.2018; S.P.Wangoleg.;studycode:DJ0588;BERMCAINS.Iso.059394•soldier,worker;Mbaïki;3°55′N, 18°0′E;24Apr.2018;S.P.Wangoleg.;studycode:DJ0595;BERMCAINS.Iso.059389•soldier, worker;Mbaïki;3°55′N,18°0′E;24Apr.2018;S.P.Wangoleg.;studycode:DJ0596;GenBankno PQ679247(mitogenome);BERMCAINS.Iso.059396•soldier,worker,♀(alate);Bondoé;5°10.3′N, 17°44.2′E;26Apr.2018;S.P.Wangoleg.;studycode:DJ0589;GenBanknosMN646738(COI), MN685943 (COII), MN686004 (28S);BERMCAINS.Iso.059393•soldier,worker,♀(alate);Bondoé; 5°10.3′N,17°44.2′E;26Apr.2018;S.P.Wangoleg.;studycode:DJ0590;GenBanknoPQ679244 (mitogenome);BERMCAINS.Iso.059390•soldier,worker,♂(alate);Bondoé;5°10.3′N,17°44.2′E; 26 Apr. 2018; S.P. Wango leg.; study code: DJ 0591; GenBank no PQ679206 (mitogenome); BE RMCA INS.Iso.059392•soldier,worker;Bondoé;5°10.3′N,17°44.2′E;26Apr.2018;S.P.Wangoleg.;study code: DJ 0594; GenBank no PQ679201 (mitogenome); BE RMCA INS.Iso.059391 • soldier, worker, European Journal of Taxonomy 1024: 1–197 (2025) 130 ♂(king);Bangui?;4°21′N,18°30′E;3May2007;N.Sionleg.;studycode:DJ0936;GenBankno PV564647 (mitogenome); BE RMCA INS.Iso.059398. CHAD•soldier,worker;Moundou;8°24′N,16°24′E;23May1948;P.-P.GrasséandC.Noirotleg.; study code: DJ 0431; MNHN EP9923. CÔTED’IVOIRE•soldier;6kmEofOdienné;9°30′N,7°30′W;Dec.1938;P.-P.Grasséleg.;study code:DJP154;MNHNEP9925•soldier;6kmEofOdienné;9°30′N,7°30′W;Dec.1938;P.-P.Grassé leg.;studycode:DJP155;MNHNEP9926•soldier;Odienné;7°15′N,7°14′W;Dec.1938;P.-P.Grassé leg.;studycode:DJP156;MNHNEP9927•soldier;MontTonkui;7°24′N,7°9′W;18Mar.1947;C. Noirotleg.;studycode:DJP338;MNHNEP9953•soldier;Ferkessédougou;9°35′N,5°12′W;2Oct. 1947;C.Noirotleg.;studycode:DJP192;MNHNEP9940•soldier;Bouaké–Mbayakroroad;7°40′N, 4°54′W;8Oct.1947;C.Noirotleg.;studycode:DJP332;MNHNEP9947•soldier,worker;Youhouli; 5°25′N,4°29′W;7Sep.1953;M.Lüscherleg.;studycode:DJ0330;initiallyC. severus; AMNH • soldier;Yapo;5°44′N,4°5′W;26May1960;C.Noirotleg.;studycode:DJP323;MNHNEP9861• soldier,♀(alate);Kpouébo(OrumboBoka);6°21′N,4°53.7′W;30Oct.1960;C.Noirotleg.;study code:DJP346;MNHN•soldier,♂(alate);Adiaké;5°27′N,3°15.5′W;15Apr.1963;C.Noirotleg.; studycode:DJP349;MNHN•soldier;Dabou;5°19′N,4°20′W;10Jun.1964;P.Bodotleg.;studycode: DJ U014; initially C. severus;NHMUK13671954•soldier;Dabou;5°19′N,4°20′W;10Jun.1964; P. Bodot leg.; study code: DJ U015; initially C. severus;NHMUK13671953•worker;Taï;5°52′N, 7°20′W;1970;C.Kerdelhuéleg.;studycode:DJ0749;GenBanknoPQ679224(mitogenome);MNHN EP9942•soldier,worker;Taï;5°52′N,7°20′W;1970;C.Kerdelhuéleg.;studycode:DJ0750;GenBank noPQ679242(mitogenome);MNHNEP9943•soldier,worker,♂(alate);Pakobo(Lamtoresearch centre);6°12′N,4°59′W;8Mar.2010;K.Dossoleg.;studycode:DJ0017;BERMCAINS.Iso.059385• soldier,worker;Pakobo(Lamtoresearchcentre);6°12′N,4°59′W;8Mar.2010;K.Dossoleg.;study code:DJ0066;BERMCAINS.Iso.059386•soldier,worker;Pakobo(Lamtoresearchcentre);6°12′N, 4°59′W;8Mar.2010;K.Dossoleg.;studycode:DJ0069;BERMCAINS.Iso.059387•soldier,worker, ♀(alate),♂(alate);Korhogo;9°24′N,5°37′W;2013;T.Coulibalyleg.;studycode:DJ0044;BERMCA INS.Iso.059411•soldier;Korhogo;9°24′N,5°37′W;2013;T.Coulibalyleg.;studycode:DJ0056; BERMCAINS.Iso.059441•soldier,worker;Youhouli;5°26.433′N,4°29.351′W;18Feb.2015;G. Josensleg.;studycode:DJ0408;BERMCAINS.Iso.059439•soldier,worker;Youhouli;5°26.417′N, 4°29.333′W;18Feb.2015;G.Josensleg.;studycode:DJ0410;GenBanknoPQ679209(mitogenome); BERMCAINS.Iso.059440•soldier,worker;Pakobo(Lamtoresearchcentre);6°12.56′N,4°58.584′W; 21 Feb. 2015; G. Josens leg.; study code: DJ 0411; GenBank no PQ679169 (mitogenome); BE RMCA INS.Iso.059415•soldier,worker;Taabo;6°17.87′N,5°0.129′W;21Feb.2015;G.Josensleg.;study code: DJ 0409; GenBank nos MN646736 (COI), MN685941 (COII), MN686002 (28S); BE RMCA INS.Iso.059455•soldier,worker;Katiola;7°58.6′N,5°4′W;26Feb.2015;G.Josensleg.;studycode: DJ0260;BERMCAINS.Iso.059413•soldier,worker;Odienné;9°26.252′N,7°34.935′W;26Feb. 2015;G.Josensleg.;studycode:DJ0414;BERMCAINS.Iso.059444•soldier,worker,♀(queen);Man; 7°24.7′N,7°35.1′W;27Feb.2015;G.Josensleg.;studycode:DJ0261;BERMCAINS.Iso.059416• soldier,worker,♂(king),♀(queen);Zéalé;5°57.9′N,8°11.4′W;28Feb.2015;G.Josensleg.;study code:DJ0262;BERMCAINS.Iso.059442•soldier,worker;Zéalé;6°57.879′N,8°11.386′W;28Feb. 2015; G. Josens leg.; study code: DJ 0415; GenBank no PQ679171 (mitogenome); BE RMCA INS. Iso.059443•soldier,worker;RouteMan–Duékoué;6°50.051′N,7°24.53′W;1Mar.2015;G.Josens leg.; study code: DJ 0413; GenBank nos MN646737 (COI), MN685942 (COII), MN686003 (28S), PQ679236 (mitogenome); BE RMCA INS.Iso.059451. GABON•soldier;LaLopéN.P.;0°15′S,11°35′E;15Mar.1998;M.Harryleg.;studycode:DJP251; MNHN EP9945. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 131 GAMBIA•soldier,♂(king);TaboKotor;13°24′N,16°40′W;10Sep.1966;W.A.Sandsleg.;study code: DJ U100; initially C. gaigei;NHMUK13671897•soldier,♂(king);Bathurst[=Banjul]–Yundum road;13°28′N,16°38′W;12Sep.1966;W.A.Sandsleg.;studycode:DJU103;initiallyC. gaigei; NHMUK13671898•soldier;Sanyangh–Gunjurroad;13°15′N,16°46′W;16Sep.1966;W.A.Sands leg.; study code: DJ U108; initially C. gaigei;NHMUK13671885•soldier,worker,♀(queen);Bathurst [=Banjul];13°13′N,16°19′W;18Sep.1966;W.ASandsleg.;studycode:DJ0717;initiallyC. gaigei; NHMUK13671896•soldier;Bakau;13°28′N,16°40′W;17Nov.1973;R.M.C.WilliamsandR.W. Lamb leg.; study code: DJ U007; initially C. severus; NHMUK 13671950 • soldier; Jambanjeli; 13°17′N,16°44′W;25Nov.1973;R.W.Lambleg.;studycode:DJU018;initiallyC. severus; NHMUK13671952•soldier;Abukogamereserve;13°24′N,16°39′W;5Dec.1973;R.M.C.Williams and R.W. Lamb leg.; study code: DJ U008; initially C. severus;NHMUK13671951•soldier,♂(king); Abukogamereserve;13°24′N,16°39′W;5Dec.1973;R.M.C.WilliamsandR.W.Lambleg.;study code: DJ U017; initially C. severus;NHMUK13671949•soldier,worker;Brikama(NyambaiForest?); 13°18′N,16°40′W;1Nov.2013;A.Ndiayeleg.;studycode:DJ0220;BERMCAINS.Iso.059397. GHANA•soldier,♀(queen);Larabanga–Sawlaroad;9°13′N,1°55′W;22Feb.1959;W.A.Sandsleg.; study code: DJ U115; initially C. gaigei;NHMUK13671882•soldier;Bolgatanga;10°34′N,0°50′W; 9 Mar. 1959; W.A. Sands leg.; study code: DJ U030; initially C. severus; NHMUK 13671966 • soldier; Tumu;11°5′N,2°17′W;16Mar.1959;W.A.Sandsleg.;studycode:DJU027;initiallyC. severus; NHMUK13671970•soldier;Lawra;10°39′N,2°52′W;18Mar.1959;W.A.Sandsleg.;studycode: DJ U031; initially C. severus;NHMUK13671967•soldier;Tamale–Yejiroad;8°55′N,0°30′W;27 Mar. 1959; W.A. Sands leg.; study code: DJ U024; initially C. severus; NHMUK 13671969 • soldier, ♀(queen);AkumadanonWenchi–Kumasiroad;7°28′N,1°58′W;1Apr.1959;W.A.Sandsleg.;study code: DJ U101; initially C. gaigei;NHMUK13671883•soldier,♀(queen);AkumadanonWenchi– Kumasiroad;7°28′N,1°58′W;1Apr.1959;W.A.Sandsleg.;studycode:DJU102;initiallyC. gaigei; NHMUK13671885•soldier;Nakpanduri;10°34′N,0°17′W;6Jun.1959;W.A.Sandsleg.;studycode: DJ U023; initially C. severus;NHMUK13671968•soldier;Ejura;7°23′N,1°22′W;20Oct.1966; W.A. Sands leg.; study code: DJ U020; initially C. severus;NHMUK13671971•soldier,♀(alate); Kumasi–Sunyani;6°53′N,1°52′W;12Jul1975;R.M.C.Williamsleg.;studycode:DJU116;initially C. gaigei; NHMUK 13671895. GUINEA•♀(alate),♂(alate);“LaMéforest”;9°31.5′N,13°41.1′W;31Jan.1931;P.-P.Grasséleg.; study code: DJ 0429; initially C. fungifaberinMNHN;MNHNEP9921•soldier;Camayenne;9°31.5′N, 13°41.1′W;1934;P.-P.Grasséleg.;studycode:DJ0427;MNHNEP9920•soldier,worker,♀(queen); Camayenne;9°31.5′N,13°41.1′W;1934;P.-P.Grasséleg.;studycode:DJ0430;MNHNEP9922• soldier,♂(alate);Nzo;7°41′N,8°19′W;25Mar.1947;C.Noirotleg.;studycode:DJP322;MNHN EP9924•soldier,♀(alate);Nzo;7°41′N,8°19′W;26Mar.1947;C.Noirotleg.;studycode:DJP343; MNHN•soldier,♀(queen);Nzo;7°41′N,8°19′W;27Mar.1947;C.Noirotleg.;studycode:DJP342; MNHN•soldier;Nimbamountain;10°0′N,13°0′W;Apr.1996;M.Harryleg.;studycode:DJ0751; MNHNEP9944•soldier;Foulaya;10°0′N,12°50′W;20Jun.1996;F.L.Guilavoguileg.;studycode: DJ 0068; initially C. severusinRMCA;BERMCAINS.Iso.059421•soldier;Forécariah;9°28′N, 13°6′W;21Jun.1996;O.Dialloleg.;studycode:DJ0067;initiallyC. severus in RMCA; BE RMCA INS.Iso.059420•soldier,worker;Haut-NigerN.P.;10°14.43′N,10°27.67′W;22Dec.1996;M.Mei leg.; study code: DJ 0314; initially C. severus; MURS. LIBERIA•soldier,♀(alate);unknownlocation;7°0′N,10°0′W;12Feb.1975;G.Beckerleg.;study code: DJ U009; initially C. severus; NHMUK 13671957. NIGERIA•soldier,♂(alate);EnuguTownship;6°27′N,7°32′E;13Feb.1955;W.V.Harrisleg.; study code: DJ U106; initially C. gaigei;NHMUK13671893•soldier;Kaduna;10°15′N,7°50′E; European Journal of Taxonomy 1024: 1–197 (2025) 132 15 Feb. 1957; W.A. Sands leg.; study code: DJ U025; initially C. severus; NHMUK 13671974 • soldier, ♂(alate);KweiHill,Heipang;9°39′N,8°50′E;29Mar.1957;W.A.Sandsleg.;studycode:DJU026; initially C. severus;NHMUK13671977•soldier,worker,♂(alate);Ropp;9°30′N,8°55.7′E;3 Apr. 1957; W.A. Sands leg.; study code: DJ 0545; initially C. severus;NHMUK•soldier,♂(alate); Bauchi–Gomberoad;10°17′N,9°56′E;7May1957;W.A.Sandsleg.;studycode:DJU105;initially C. gaigei;NHMUK13671890•soldier;Donkin;8°37′N,11°44′E;24May1957;W.A.Sandsleg.; study code: DJ U028; initially C. severus;NHMUK13671972•soldier;Wamba;9°31′N,8°37′E;23 Feb. 1958; W.A. Sands leg.; study code: DJ U022; initially C. severus; NHMUK 13671973 • soldier, ♂(alate);Gboko–Otupkoroad;7°17′N,8°54′E;26Feb.1958;W.A.Sandsleg.;studycode:DJU032; initially C. severus;NHMUK13671976•soldier,♀(queen);Kabba–Ondoroad;7°34.75′N,5°48′E; 2 Mar. 1958; W.A. Sands leg.; study code: DJ U107; initially C. gaigei; NHMUK 13671889 • soldier, ♂(alate);Enugu–Onitsharoad;6°25′N,7°24′E;3Mar.1958;W.A.Sandsleg.;studycode:DJU113; initially C. gaigei;NHMUK13671892•soldier,♂(alate);Enugu–Otukporoad;6°45′N,7°28′E;5Mar. 1958; W.A. Sands leg.; study code: DJ U112; initially C. gaigei; NHMUK 13671891 • soldier, worker; Dekina;7°40.25′N,6°56′E;7Mar.1958;W.A.Sandsleg.;studycode:DJ0659;initiallyC. gaigei; NHMUK13671993•soldier,♀(alate);Lokoja;7°50′N,6°33′E;10May1958;W.A.Sandsleg.;study code: DJ U029; initially C. severus;NHMUK13671975•soldier;MayoNdaga;6°55′N,11°27′E;ca 1975; J.T. Medler leg.; study code: DJ U021; initially C. severus; NHMUK 13671978. SIERRALEONE•soldier,worker,♀(alate);unknownlocation;8°0′N,12°0′W;14Jun.1917;P.A. Buxton leg.; study code: DJ 0323; initially C. silvestrii;AMNH•soldier;Njala;8°6′N,12°4′W; 24 Aug. 1930; E. Hargreaves leg.; study code: DJ U019; initially C. severus; NHMUK 13671979 • soldier,worker;Njala;8°10′N,12°24′W;24Aug.1930;E.Hargreavesleg.;studycode:DJ0325; initially C. silvestrii;AMNH•soldier,worker;Njala;8°10′N,12°24′W;24Aug.1930;E.Hargreaves leg.; study code: DJ 0540; initially C. silvestrii;NHMUK•soldier,worker;Njala;8°10′N,12°24′W; Apr. 1936; E. Hargreaves leg.; study code: DJ 0546; initially C. severus; NHMUK • soldier, worker, ♂(alate),♀(queen);Njala;8°10′N,12°24′W;29May1947;F.A.Squireleg.;studycode:DJ0326; initially C. silvestrii;AMNH•soldier;Freetownairport;8°37′N,13°11′W;Jan.1955;W.V.Harris leg.; study code: DJ U011; initially C. severus;NHMUK13671960•soldier;Njala;8°6′N,12°4′W; 27 Jan. 1955; W.V. Harris leg.; study code: DJ U013; initially C. severus; NHMUK 13671964 • soldier;Freetown;8°25′N,13°13′W;Feb.1955;W.V.Harrisleg.;studycode:DJU002;initially C. severus;NHMUK13671959•soldier;Freetown;8°25′N,13°13′W;Feb.1955;W.V.Harrisleg.; study code: DJ U003; initially C. severus;NHMUK13671961•soldier,worker,♀(queen);Freetown; 8°28′N,13°15′W;27May1956;J.K.OclooandR.M.C.Williamsleg.;studycode:DJ0544;initially C. severus;NHMUK•soldier;Freetown;8°28′N,13°15′W;8Jan.1958;W.Wilkinsonleg.;study code: DJ U005; initially C. severus;NHMUK13671965•soldier;Freetown;8°28′N,13°15′W;8 Jan. 1958; W. Wilkinson leg.; study code: DJ U012; initially C. severus; NHMUK 13671960 • soldier; “Boresidential”;7°57′N,11°44′W;10Jan.1958;W.Wilkinsonleg.;studycode:DJU010;initially C. severus;NHMUK13671963•soldier;Makeni;8°53′N,12°2′W;24Sep.1966;W.A.Sandsleg.; study code: DJ U004; initially C. severus; NHMUK 13671958. TOGO•soldier;Kloto;6°57.17′N,0°34.21′E;8Dec.2018;G.Goergenleg.;studycode:DJBB01; BERMCAINS.Iso.059380•soldier;Kloto;6°57.17′N,0°34.21′E;8Dec.2018;G.Goergenleg.; studycode:DJBB02;BERMCAINS.Iso.059381•soldier;Kloto;6°57.17′N,0°34.21′E;8Dec. 2018;G.Goergenleg.;studycode:DJBB03;BERMCAINS.Iso.059383•soldier;Kloto;6°57.17′N, 0°34.21′E;8Dec.2018;G.Goergenleg.;studycode:DJBB04;BERMCAINS.Iso.059384•soldier; Kloto;6°57.17′N,0°34.21′E;8Dec.2018;G.Goergenleg.;studycode:DJBB05;BERMCAINS. Iso.059382•soldier,worker;Kloto;6°57.15′N,0°34.2′E;8Dec.2018;G.Goergenleg.;studycode: DJ0635;BERMCAINS.Iso.059454•soldier,worker;Kloto;6°57.15′N,0°34.2′E;8Dec.2018;G. Goergen leg.; study code: DJ 0636; BE RMCA INS.Iso.059453 • soldier; PN Fazao-Malfakassa, Bonako; JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 133 9°10.08′N,0°57′E;17Feb2025;Y.Roisinleg.;studycode:DJY383;BERMCAINS.Iso.059952• soldier;RouteAtakpamé–Badou;7°32.4′N,1°0′E;19Feb2025;Y.Roisinleg.;studycode:DJY381; BERMCAINS.Iso.059950•soldier;RouteAtakpamé–Badou;7°33.24′N,1°0.54′E;19Feb2025;Y. Roisin leg.; study code: DJ Y382; BE RMCA INS.Iso.059951. Historical review ThefirstmentionofanIsognathotermes species in the literature probably dates back to Smeathman (1781): of two mushroom-shaped nest-building species, “The largest species, the Termes atrox, in its perfect state measures one inch and three-tenths from the extremities of the wings on the one side to the extremities to the other”. As Smeathman collected in Sierra Leone, this dimension (~33 mm) is entirely compatible with the wing dimensions of I. severus found in West Africa. However, Smeathman’s material could not be traced even in the early 20th century (Sjöstedt 1926: 218) and is therefore considered lost and unavailable for a systematic revision. Silvestri (1914: 92–93) described this species under the name Cubitermes severus. He provided a descriptionofqueen,soldier,andworkertogetherwithmeasurementsandfigures.Inthesamepaper,he described Cubitermes severus var. modestior (1914: 93–94); he mentioned that the soldiers and imagines are like the typical form (= Cubitermes severus) but smaller. Sjöstedt (1926: 250–251) housed C. severusinthesub-familyTermitinaeandprovidedafirstdescription of alates. Sjöstedt (1926: 238–239) considered that C. severus var. modestior deserved to be elevated to the species level. He referred to it under the name C. modestior, housed it in the sub-family Termitinae, and included it in a “glebae-Gruppe” of small Cubitermes species. He also included C. severus in his soldier’s key of Cubitermes species and inserted it in a “bulbifrons-Gruppe” of species with an upwards humped frons. Snyder (1949: 163) catalogued C. severus and C. modestior and housed them in the sub-family Termitinae. Krishna et al. (2013: 1936) housed C. severus and C. modestior in the sub-family Cubitermitinae. Josens & Deligne (2019: 39–42) placed these species within the fungifaber valve pattern group. Hellemans et al. (2021: 233) placed these species in the restored genus Isognathotermes. The small size of I. modestior might suggest a very young colony, but this is excluded with a physogastric queen; this small size could also be the result of environmental conditions. As I. modestior is known from a single nest, without the aid of sequencing (old sample), there is still some doubt as to its status (abnormalsampleordistinctspecies?).Onthebasisofmorphologyalone,sincethetypematerialof I. modestior (Silvestri, 1914) is now included among the smallest specimens of I. severus, it is now considered a junior synonym of Isognathotermes severus (Silvestri, 1914). Redescription Imago C olour . Head capsule: well sclerotised, fresh samples very dark, C6–C8 (but C4–C6 in long preserved imagines); fontanelle concolorous with head capsule or paler (up to two levels). Postclypeus C6– C7 slightly paler than head capsule. Antennae C4–C6 without any difference between proximal and distal articles. Thorax: pronotum C6–C7 (paler in long preserved samples), as postclypeus, generally somewhat paler than head capsule; mesoand metanotum C4–C7, sometimes somewhat paler than pronotum. Legs C3–C5; tibia usually slightly (one level) darker than femur. Wings hyaline with brown European Journal of Taxonomy 1024: 1–197 (2025) 134 to grey tinge (Cf2–Cf4), anterior veins darker. Abdomen: tergites C5–C7. Sternites appreciably paler in middle (C3–C4) with both sides darker (C4–C6); posterior sternites darker (C4–C6) than anterior. Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat40×,sometimes onlyat80×.Legsverypilose,furnished(amongnumerousfinesetae)withsomestrongersetae:7–12 on the carina of fore coxa and 0–8 on the ventral side of fore coxa; fore trochanter with some strong setae; tibia pilose fore, mid, and hind tibia furnished with 10–30 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Table 14; Figs 26, 61). Size: the imagines of I. severus are, on average, medium to large sized in the genus Isognathotermes (Fig. 26). Head capsule: compound eyes round to shortly oval; ocelli shortly to strongly oval, removed from eyes by a distance equal to 0.4–1.3 ocellus small diameter; fontanelle generally a tiny round or elongate marking. Antennae: 16 articles on alate individuals, always shortened by amputation by two to four articles in queens and kings. Labrum: cupola shaped, wider than long. Left mandible with apical tooth on average medium sized in the genus and alwaysmoreprominentthanfirstmarginal;marginalteeththreeinnumberbutsecondoneonlysuggested byanundulationofedgebetweenfirstandthirdmarginalteeth;onlytheapicaltoothisacuteinunworn specimens; premolar tooth with proximal end obscured or partly obscured by molar prominence in dorsal view; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandiblewithapicaltoothalwaysmoreprominentthanfirstmarginal;marginal teeth twoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhenfresh;secondmarginaltooth smallerandwithablunttipevenwhenfresh;molartoothbearingaventralroundedflangeandending posteriorly in a kind of heel. Thorax: pronotum appreciably wider than long and narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly Fig. 61. Isognathotermes severus (Silvestri, 1914) and junior synonym species: imagines. Lateral and dorsal views of an imago’s head capsule, and dorsal view of this imago’s mandibles. A. Of the queen from type colony of Cubitermes severus Silvestri, 1914 (DJ 0609). B. Of the king from type colony of Cubitermes severus var. modestior Silvestri, 1914 (DJ 0294). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 135 elevated. Fore coxaflangedventrallyresultinginacarina.Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 2–4 and 8–13 branches, respectively. Gut (only studied in some cases): enteric valve weakly developed and hardly comparable with workers’ and soldiers’ valves; odd PCs are slightly longer than even PCs. Caecum present as a small amorphous button. Soldier Colour. Head capsule generally tending towards deep palette (Cd3–Cd6); there is always a gradient from a darker frons to a paler back, smooth and extended in 72% of the samples examined but more abrupt in the remaining 28% giving in some cases the impression that the head capsule is bicolorous (as in Fig. 13). Antennae and labrum concolorous with or one level paler than head capsule. Mandibles dark (C6–C8) generally with an abrupt clearing on their bases (two palette levels) which is generally the same Table 14. Isognathotermes severus(Silvestri,1914):rangesofsignificantmeasuresinthethreecastes, in alphabetical orders of the “Code” column. Variable *Code *Range Type Imagines (n = 61) Raw measures (mm) Eye: large diameter IEyD0.34–0.58 0.48 Head: width across the eyes IHdW 1.49–1.79 1.71 Left mandible: A-m1 distance IMlAmD 0.18–0.26 0.20 Ocellus: large diameter IOcD0.15–0.23 0.22 Postclypeus: width IPcW 0.70–0.86 0.79 Pronotum: maximal width IPnW 1.31–1.60 1.50 Hind tibia: length IT3L 1.66–2.27 1.97 Wing: length (n = 31) IWgL 12.2–17.3 NA Index Left apico-marginal index IMlAmD/IMlmmD 1.00–1.76 1.12 Soldiers (n = 161) Raw measures (mm) Head: upper sagitta SHdC 0.00–0.09 0.05 Head: length SHdL 2.43–3.29 2.96 Head: width SHdW 1.76–2.31 2.02 Left mandible: lesser sagitta SMlc 0.14–0.31 0.19 Left mandible: ventral length SMlL 2.07–2.58 2.33 Hind tibia: length ST3L 1.52–1.93 1.75 Indices Head elongation index SHdL/SHdW 1.22–1.57 1.47 Left mandible: apical curvature index SMlc/SMlL 0.06–0.13 0.08 Mandibles: curvature symmetry SMlc/SMrc 0.79–1.24 0.90 Workers (n = 92 Raw measures (mm) Head: width WHdW 1.06–1.36 1.25 Left mandible: A-m1 distance WMlAmD 0.15–0.22 0.18 Left mandible: total length WMlL 0.51–0.65 0.60 Hind tibia: length WT3L 1.11–1.48 1.33 Valve: PC average length WVP-AvL 0.51–0.85 0.67 Valve: PC average width WVP-AvW 0.05–0.10 0.08 Valve: SC average length WVS-AvL 0.42–0.70 0.55 Valve: SC average width WVS-AvW 0.22–0.43 0.30 Index Valve: odd PC elongation index WVPOdd-Elg 6.78–12.7 8.85 *Abbreviations:seedefinitionsinMaterialandmethods. European Journal of Taxonomy 1024: 1–197 (2025) 136 colour as frons. Thorax and legs paler than head capsule (C2–C4). Abdomen grey to red-brown owing to digestive bolus, sometimes with a yellow tinge on tergites. Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremity of distalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore).Labrum always with 5–8 large setae on each lobe. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs:forecoxabearsatleastonefinesetaandgenerally0–3spinesoncarinaand generally not any spine (rarely 1–2) on ventral side; trochanter generally with some long lined-up setae, sometimes with 6–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 6–17 strong setae or spines along their shaft. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 14; Fig. 62). Size: the soldiers of I. severus are medium sized in the genus Isognathotermes (Figs 21, 28). Head capsule: always clearly sclerotised; appreciably longer Fig. 62. Isognathotermes severus (Silvestri, 1914) and junior synonym species: soldiers. Lateral and dorsal views of a soldier’s head capsule; ventral view of its mandibles; and dorsal view of its labrum. A. From the type colony of Cubitermes severus Silvestri, 1914 (DJ 0609). B. From the type colony of Cubitermes severus var. modestior Silvestri, 1914 (DJ 0294). C. From the type colony of Cubitermes silvestrii Sjöstedt, 1925 (DJ 0302). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 137 than wide. Dorsal view: lateral sides mostly subparallel always with a narrowing near posterior third or fourth, from antennal sockets sides converge clearly towards bases of mandibles; posterior side regularly roundedorsometimeswithashortstraightorevenconcavepartinthemiddle.Upperprofilealmost always slightly to strongly concave; angle between extended mandibles and frons varies from right to obtuse; frons generally with a sketched or small anterior hump (without any hump in 10% of the samples examined). Gulamentum in ventral view always constricted in its posterior half, with sides of anterior part either roundly convex or forming an acute widening or even a kind of ear on each side. Antennae: 14.5–15 articles). Labrum: always deeply bifurcate and wider than long, with sides varying from lyreshaped(in85%ofthesamplesexamined)toconvex;lobesangular,frequentlywithfine,whitishor translucent tips; anterior margin concave. Mandibles: sabre-like generally strongly curved; inner edges generally smooth with one distinct but very small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible equally or slightly more curved than left. Thorax: pronotum sellate, as wide as 54–64% of head width, with generally entire anterior and posterior margins. Fore coxaflangedventrallyresultinginasharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Caecum always rather small, best seen in ventral view, near centre of abdomen, lobed, rarely (in 6% of the samples examined) with a lobe expanded somewhat forward. Arrangement of enteric valve cushions showing trilateral symmetry, the odd cushions being about 16% longer than the even cushions, generally without any crest (muneris EVA pattern) or with crests very weakly developed. Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always one to two levels darker (C4–C5). Thorax, nota, and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust, scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxaalwayscarinated,bearingonefinesetaand furnished with 3–5 spines on carina and 0–4 on ventral side; fore trochanter with 5–8 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 6–15 spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 14, Fig. 63). Size: the workers of I. severus are, on average, medium sized in the genus Isognathotermes (with large overlapping on several other species: Fig. 30). Head capsule: weakly sclerotised (except mandibles). Antennae of 14 or 14.5 (rarely 15) articles. Labrum: cupola shaped. Left mandible: apical tooth well developed with a sharp tip when fresh; marginal teeththreeinnumber,firstmarginaltoothwelldevelopedbutwithablunttipevenwhenfresh,second marginal tooth faint (visible as an undulated edge and disappearing in worn mandibles), third marginal tooth with a blunt tip; premolar tooth with its proximal end generally (in 70% of the samples examined) well visible; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed with a sharp tip when fresh; marginal teethtwoinnumber;firstmarginaltoothwelldevelopedwithasharptipwhenfresh;secondmarginal toothsmallerandwithablunttipevenwhenfresh;molartoothbearingaventralroundedflangeand ending posteriorly in a kind of heel. Thorax: pronotum sellate, as wide as 57–73% of head width. Fore coxaflangedventrallyresultinginasharpcarina.Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions of the fungifaber pattern with triradial symmetry: the odd PCs, in their downstream part, are rather narrow and bear crests that are generally as high as or higher than they are wide, with long and strong bristles; however, rather frequently (in 11 cases out of 92), including the syntype from Kakoulima (but not the syntype from European Journal of Taxonomy 1024: 1–197 (2025) 144 Isognathotermes ugandensis (Fuller, 1923) Figs 26–31, 33, 65–69, distribution map: Fig. 49; Tables 16–17 Cubitermes ugandensis Fuller, 1923: 191–192. Cubitermes antennalis Sjöstedt, 1924c: 493. Mirotermes (Cubitermes) antennalis–Emerson1928:513–515,text-fig.57,plXXXIII. Cubitermes ugandensis – Sjöstedt 1926: 251–252, table 10 b1–b2. — Snyder 1949: 165. — Williams 1966:107–108,figs15,31,47,64,82.—Bouillon&Vincke1971:269.—Krishnaet al. 2013: 1942. — Josens & Deligne 2019: 60–61. Cubitermes antennalis – Williams 1966: 107–108. — Krishna et al. 2013: 1943. Cubitermes ugandensis – Hellemans et al. 2021: 233. Isognathotermes antennalis – Hellemans et al. 2021: 233. Isognathotermes ugandensis – Hellemans et al. 2021: 233. With four new subspecies: Isognathotermes ugandensis burundii Josens & Deligne subsp. nov. Isognathotermes ugandensis kenyae Josens & Deligne subsp. nov. Isognathotermes ugandensis malawii Josens & Deligne subsp. nov. Isognathotermes ugandensis ugandensis Josens & Deligne subsp. nov. Diagnosis This species is very close to I. minitabundus and I. severus. Fig. 65. PCA on imagines’ morphology involving the species of Isognathotermes Sjöstedt, 1926 with a fungifaber-typeEVA;thefirstaxisislinkedtosize,especiallythatofthemandiblesandthorax(the largest on the right), the second axis to the dimensions of the eyes and ocelli (the largest at the bottom). Abbreviations: acri = I. acristatus sp. nov.; fung = I. fungifaber; mini = I. minitabundus; seve = I. severus; ugbu = I. ugandensis burundii ssp. nov.; ugke = I. ugandensis kenyae ssp. nov.; ugma = I. ugandensis malawii ssp. nov.; ugug = I. ugandensis. ugandensis ssp. nov.; ugxx = I. ugandensis formerly known as I. antennalis; zenk = I. zenkeri. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 145 The worker (all four subspecies) has a fungifaber EVA but in 6% of the samples examined, it has an EVA intermediate between the fungifaber and finitimus patterns. Its valve is, on average, somewhat larger than that of I. minitabundus (Fig. 31). It is among the mediumto large-sized workers of the genus Isognathotermes (Fig. 30). As in I. minitabundus, the premolar tooth of the left mandible is more apparent than in most other species. The soldier (all four subspecies) is among the mediumto large-sized soldiers in the genus Isognathotermes (Fig. 28), on average somewhat larger than I. severus. It has the left mandible slightly curved to almost straight and obviously less curved than the right mandible as in I. minitabundus but more asymmetrical than in I. severus (SMlc/SMrc = 0.68–1.02, vs 0.51–1.03 in I. minitabundus and 0.79–1.24 in I. severus). Its head is generally clearly bulbous, but this is shared with I. severus (and also with I. bulbifrons which has a finitimus EVA). The imago is among the mediumto large-sized imagines of the genus Isognathotermes (Figs 26, 65). The premolar tooth on left mandible is more apparent than in most other species (but this is shared with I. severus and I. minitabundus). Contrary to usual, the morphology of imagines is more heterogeneous than that of soldiers and workers (Figs 65–69), and this heterogeneity is linked to origin and altitude (Fig. 66), revealing clear subgroups that are hardly detectable in soldiers or workers. Pending more comprehensive molecular data (most of the available samples being too old to be sequenced), we propose to distinguish four subspecies based onoverallsize(firstPCAfactor)andeyeandocellidimensions(secondPCAfactor). Etymology The name ugandensis (from Uganda and Latin desinence -ensis, from) clearly refers to the country (Uganda) of the type locality. Fig. 66. Correlation between imago size (ImDdW = imagines’ head width) and altitude (all I. ugandensis samples, n = 58, r = 0667, p<0.01). European Journal of Taxonomy 1024: 1–197 (2025) 146 Material examined See hereafter the material examined of Isognathotermes ugandensis ugandensis and other subspecies. Historical review Fuller (1923: 191–192) described this species under the name Cubitermes ugandensis. He provided descriptions of alate, imago, and soldier. Sjöstedt(1926:251–252)providedaredescriptionofalateimagoandsoldier,togetherwithfiguresofthe soldier’shead,andashortfirstdescriptionoftheworker.Sjöstedt(1926:249–250)includedCubitermes ugandensis in imagines’ and soldiers’ keys of Cubitermes species and inserted it in a “bulbifrons-Gruppe” of species with an upwards humped soldier’s frons. Snyder (1949: 165) catalogued Cubitermes ugandensis in the sub-family Termitinae. Williams (1966: 107–108) provided a detailed redescription of imago and soldier along with measurementsandfigures.HestatedthatthealateimagodescribedbyFuller(1923)andSjöstedt(1926) belonged to Ophiotermes ugandaensis. Williams (1966: 108) considered C. ugandensis as a senior synonym of C. antennalis. Emerson, in his unpublished “card catalog”, named six samples (from three nests) “Cubitermes basilewskyi” in honour of Pierre Basilewsky who collected this material in Rwanda, but it was neither described nor published (nomen nudum). Two such subsamples preserved in RMCA were examined by Williams in 1968 and considered to be Cubitermes ugandensis;confirmedinthisstudyasI. u. burundii. Bouillon & Vincke (1971: 269) described the enteric valve of C. ugandensisasbelongingtothefirstof three types, the “simple type” without any spatula. Krishna et al. (2013: 1942) housed Cubitermes ugandensis in the sub-family Cubitermitinae. Josens & Deligne (2019: 39–42) placed this species within the fungifaber valve pattern group. Hellemans et al. (2021: 233) placed this species in the restored genus Isognathotermes. Here, we divide the species I. ugandensis into four subspecies that could later become true species. The problem at this stage of our knowledge is that molecular data is still scarce; these taxa can therefore only be recognised by the morphology of the imagines (which are missing from almost half the samples) and by their geographical origin. Redescription The redescription concerns the species; the distinction between subspecies is based mainly on the imagines’ sizes and origins: see diagnosis. Imago Colour. Head capsule: well sclerotised, fresh samples very dark, C6–C8 (C6–C7 in long preserved imagines); fontanelle concolorous or almost so with head capsule. Postclypeus C5–C7 concolorous or slightly paler (one level) than head capsule. Antennae C4–C7 without any difference between proximal and distal articles. Thorax: pronotum C5–C7, as postclypeus, concolorous or slightly (one level) paler than head capsule; mesoand metanotum C5–C6, sometimes somewhat paler than pronotum. Legs C3–C5; tibia concolorous with femur or somewhat (one level) darker. Wings hyaline with brown to grey tinge (Cf2–Cf3), anterior veins darker. Abdomen: tergites C6–C7. Sternites appreciably paler in middle (C3–C4) with both sides darker (C4–C5); posterior sternites darker (C4–C5) than anterior. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 147 Setation. Head capsule,withsomeprominentsetaesetamongstahighdensityofshort,finesetae forming a dense mat. Labrum and postclypeus with some prominent setae mixed with shorter ones. Antennae with some prominent setae, some more numerous smaller setae and, mainly distally on most articles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×ormore).Thorax: pronotum with prominent setae mainly on margins and shorter ones in middle; mesoand metanotum withsomefine,palesetae,arrangedinamedio-longitudinalstrip,generallyvisibleat40–80×,these finesetaedonotextendovertheposteriormargin.Legsverypilose,furnished(amongnumerousfine setae) with some stronger setae: 7–12 on the carina of fore coxa and 1–6 on the ventral side of fore coxa and on trochanter; tibia pilose, fore, mid, and hind tibia furnished with 15–30 spines and bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively. Abdomen: tergites with many large and small setae. Sternites with long setae, erect or directed slightly forward, and many long and smaller setae directed backwards. StruCture (measurements in Tables 16–17; Fig. 67). Size: the imagines of I. ugandensis are among the mediumto large-sized species of the genus Isognathotermes (as I. minitabundus) (Fig. 26). The imagines’ size is one of the criteria that distinguish the subspecies (see diagnosis). Head capsule: compound eyes oval; ocelli shortly to moderately oval, removed from eyes by a short distance with an eye to ocellus minimal distance index: IEyOcD/IOcd = 0.54–1.58 somewhat larger than in I. severus (0.39–1.29) and smaller than in I. minitabundus (1.10–1.70); fontanelle generally a tiny round or elongate marking. Antennae: 16 articles on alate individuals, shortened by amputation by some articles in king and queen. Labrum: cupola shaped, wider than long. Left mandible with apical tooth medium to small sized(IMlAmD=0.19–0.27mm:Fig.27)andalwaysmoreprominentthanfirstmarginal;marginal teeth three in number; second marginal appearing as an undulated edge, reduced but still present in worn mandibles, third marginal tooth with a blunt tip; premolar tooth generally well visible (best seen than in most other species); only the apical tooth is acute in unworn specimens; molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible with apical toothalwaysmoreprominentthanfirstmarginal;marginalteethtwoinnumber;firstmarginaltoothwell developed with a sharp tip when fresh; second marginal tooth smaller and with a blunt tip even when fresh;molartoothbearingaventralroundedflangeandendingposteriorlyinakindofheel.Thorax: pronotum appreciably wider than long and narrower than head width (including the eyes), straight to very weakly sellate with anterior lobe short and very slightly elevated. Fore coxaflangedventrallyresulting in a carina. Wings: R1 fused entirely with costal margin, sclerotised; Rs simple, sclerotised; M and Cu not or weakly sclerotised with 2–5 and 9–12 branches, respectively. Gut not studied. Soldier Colour. Head capsule generally tending towards deep palette (Cd4–Cd6) becoming fader and somewhat darker in long preserved samples; there is generally a smooth gradient from a darker frons to a paler back. Antennae and labrum generally one to two palette levels paler than head capsule. Mandibles dark (C6–C8) generally with an abrupt clearing on their bases (one to two levels) which is generally the same colour as frons; in long preserved samples, this clearing tends to fade. Thorax and legs paler than head capsule (C3–C4) somewhat darker in long preserved samples. Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule with few scattered setae; on frons a dense bunch of setae surrounds and overhangs fontanelle. Antennae with some prominent setae, more numerous smaller setae and at distal extremityofdistalarticles,abunchofveryfine,bentsetae(visibleonlyathighmagnification,50×or more). Labrum always with 4–8 large setae on each lobe. Thorax: proand mesonotum with a small number of setae mainly located on margins. Legs:forecoxabearsatleastonefinesetaand1–3spines (exceptionally 6) on carina and not any spine on ventral side (rarely one); trochanter generally with some strong lined-up setae, or with 3–7 spines; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively (the latter sometimes weakly developed) and a row of 7–18 spines along European Journal of Taxonomy 1024: 1–197 (2025) 148 their shaft. Abdomen: tergites with some large setae, mainly or only on their posterior margins. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 16; Figs 28, 67). Size: the soldiers of I. ugandensis are part of the medium to larger soldiers in the genus Isognathotermes (Fig. 28). Head capsule: always clearly sclerotised; appreciably longer than wide. Dorsal view: lateral sides mostly subparallel with a clear narrowing near posterior third or fourth, from antennal sockets sides converge towards bases of mandibles;posteriorsideregularlyconvexorsometimeswithshortstraightparts.Upperprofilealways Fig. 67. Isognathotermes ugandensis (Fuller, 1923): imago and soldier. A. Lateral and dorsal views of the head capsule and dorsal view of the mandibles of an alate male of I. ugandensis ugandensis ssp. nov.; from a non-type colony (DJ 0570). B. Of an alate female from the type colony of Cubitermes antennalis Sjöstedt, 1924 (DJ 0031). C. Lateral and dorsal views of a soldier’s head capsule, ventral view of its mandibles, and dorsal view of its labrum from the type colony of Cubitermes ugandensis Fuller, 1923 (DJ 0289). D. From the type colony of Cubitermes antennalis Sjöstedt, 1924 (DJ 0013). JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 149 rather strongly concave; angle between extended mandibles and frons obtuse; frons with sketched to clear anterior hump. Gulamentum in ventral view always constricted in its posterior half, with sides of anterior part generally forming an acute widening or even a kind of ear on each side. Antennae: of 14–15 articles. Labrum: always deeply bifurcate and wider than long, with sides varying from lyre-shaped (in 90%ofthesamplesexamined)toconvex;lobesangular,generallywithfine,whitish,ortranslucenttips; anterior margin concave. Mandibles: sabre-like and rather clearly asymmetrical (but a little less than in I. minitabundus), the left mandible is slightly curved and obviously less curved than the right mandible; inner edges generally smooth with one distinct but very small marginal tooth, near molar tooth on each mandible; mandibles clearly shorter than head; entire surface of both mandibles smooth and glossy. Right mandible always clearly more curved than left. Thorax: pronotum sellate, as wide as 54–61% of Table 16. Isognathotermes ugandensis(Fuller,1923):rangesofsignificantmeasuresinthethreecastes, in alphabetical orders of the “Code” column. Variable *Code *Range Type Imagines (n = 59) Raw measures (mm) Eye: large diameter IEyD0.39–0.57 NA Head: width across the eyes IHdW 1.57–1.84 NA Left mandible: A-m1 distance IMlAmD 0.19–0.27 NA Ocellus: large diameter IOcD0.15–0.23 NA Postclypeus: width IPcW 0.68–0.93 NA Pronotum: maximal width IPnW 1.22–1.74 NA Hind tibia: length IT3L 1.47–2.31 NA Wing: length (n = 32) IWgL 13.7–19.4 NA Index Left apico-marginal index IMlAmD/IMlmmD 0.93–1.71 NA Soldiers (n = 86) Raw measures (mm) Head: upper sagitta SHdC 0.01–0.10 0.07 Head: length SHdL 2.73–3.72 3.32 Head: width SHdW 1.86–2.37 2.29 Left mandible: lesser sagitta SMlc 0.12–0.27 0.23 Left mandible: ventral length SMlL 2.15–2.74 2.56 Hind tibia: length ST3L 1.57–1.88 1.86 Indices Head elongation index SHdL/SHdW 1.35–1.62 1.45 Left mandible: apical curvature index SMlc/SMlL 0.06–0.10 0.09 Mandibles: curvature symmetry SMlc/SMrc 0.68–1.02 0.83 Workers (n = 45) Raw measures (mm) Head: width WHdW 1.11–1.42 1.17 Left mandible: A-m1 distance WMlAmD 0.16–0.22 0.19 Left mandible: total length WMlL 0.53–0.67 0.58 Hind tibia: length WT3L 1.10–1.49 1.35 Valve: PC average length WVP-AvL 0.62–0.85 0.64 Valve: PC average width WVP-AvW 0.06–0.12 0.07 Valve: SC average length WVS-AvL 0.55–0.73 0.58 Valve: SC average width WVS-AvW 0.30–0.45 0.33 Index Valve: odd PC elongation index WVPOdd-Elg 5.57–12.1 10.4 *Abbreviations:seedefinitionsinMaterialandmethods. European Journal of Taxonomy 1024: 1–197 (2025) 150 head width, with straight or indented anterior margin and posterior straight margin. Fore coxaflanged ventrally resulting in a sharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Caecum always rather small, best seen in ventral view, near centre of abdomen, generally three-lobed. Arrangement of enteric valve cushions showing trilateral symmetry, the odd cushions being about 16% longer than the even cushions, generally without any crest or with crests very weakly developed. Worker Colour. Head capsule pale (C1–C3) turning grey in long preserved samples. Antennae: proximal articles pale (C2–C3), distal articles always one to two levels darker (C4–C5). Thorax, nota, and legs pale (C1–C3). Abdomen grey to red-brown owing to digestive bolus. Setation. Head capsule and postclypeus with few, erect, scattered setae. Labrum with few, robust scattered setae. Antennae with some prominent setae, some more numerous smaller setae and at distal extremityofdistalarticles,abunchoffine,bentsetae(visibleonlyathighmagnification,50×ormore). Thorax: nota with some scattered setae. Legs:forecoxaalwayscarinated,bearingonefinesetaand furnished with 3–5 spines on carina and 0–2 on ventral side; fore trochanter with 6–7 spines, all except one lined up; fore, mid, and hind tibia bearing 3, 2, 2 apical spurs and 0, 2, 0 subapical spurs respectively and a row of 7–16 spines. Abdomen: tergites with scattered setae. Sternites with long setae, erect or slightly directed forward, often coloured, and smaller setae directed backwards. StruCture (measurements in Table 16, Figs 30, 67). Size: the workers of I. ugandensis are part of the medium to larger workers in the genus Isognathotermes (but with large overlapping on several other species: Fig. 30). Head capsule: weakly sclerotised (except mandibles). Antennae of 14 or more often 14.5 articles. Labrum: cupola shaped. Left mandible: apical tooth well developed with a sharp tip when fresh;marginalteeththreeinnumber,firstmarginaltoothwelldevelopedbutwithablunttipevenwhen fresh, second marginal appearing as an undulated edge, reduced but still present in worn mandibles Table 17. New subspecies of Isognathotermes ugandensis(Fuller,1923):significantmeasurementranges in the imago caste. Mean altitude 1015 m 1350 m 1560 m 2200 m Code *Range ugandensis n = 45** Range burundii n = 5 Range malawii n = 5 Range kenyae n = 3 IEyD0.40–0.57 0.39–0.46 0.42–0.44 0.41–0.45 IHdW 1.57–1.74 1.62–1.72 1.65–1.78 1.72–1.84 IMlAmD 0.19–0.25 0.20–0.23 0.23–0.27 0.20–0.23 IOcD0.15–0.23 0.15–0.18 0.15–0.18 0.15–0.18 IPcW 0.68–0.86 0.77–0.86 0.84–0.91 0.85–0.93 IPnW 1.22–1.60 1.41–1.55 1.58–1.71 1.61–1.74 IT3L 1.47–2.31 1.98–2.12 2.00–2.07 2.07–2.20 IWgL 13.6–18.1 15.6–17.5 NA 18.9–19.5 IMlAmD/ IMlmmD 1.10–1.64 1.02–1.34 1.18–1.71 0.93–1.20 IEyD/IHdW 0.25–0.34 0.24–0.28 0.24–0.27 0.23–0.25 *Abbreviations:seedefinitionsinMaterialandmethods. ** Including 14 individuals previously known as I. antennalis. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 151 (better seen than in other species), third marginal tooth with a blunt tip; premolar tooth generally well visible (also better seen than in other species); molar tooth bearing a rounded molar prominence dorsally and ending posteriorly in a tiny acute apophysis. Right mandible: apical tooth well developed with a sharp tip when fresh and sometimes with a wavy inner edge near the base; marginal teeth two in number; firstmarginaltoothwelldevelopedwithasharptipwhenfresh;secondmarginaltoothsmallerandwith ablunttipevenwhenfresh;molartoothbearingaventralroundedflangeandendingposteriorlyina kind of heel. Thorax: pronotum sellate, as wide as 60–68% of head width. Fore coxaflangedventrally resulting in a sharp carina. Gut: enteric valve seating on left side, best seen in ventral view, situated in second half of abdomen. Arrangement of enteric valve cushions of the fungifaber pattern with triradial symmetry: the odd PCs, in their downstream part, are rather narrow and bear crests that are as high as or higher than they are wide, with long and strong bristles (but in 6% of the samples examined, the EVA is intermediate between the fungifaber and finitimus patterns); 16–27 supporting bristles on each side of the odd PCs; secondary cushions are wide at the upstream end, narrowing noticeably downstream with a homogeneous spine scattering. Caecum always rather small, visible in ventral view, near centre of abdomen, generally with two short lobes. Fig. 68. Isognathotermes ugandensis (Fuller, 1923): soldier, and worker. A. PC1s of soldier’s and worker’s enteric valves (with another worker’s PC in side view), caecum and foreleg of this worker from a non-type colony (DJ 0570). B. From the type colony of Cubitermes antennalis Sjöstedt, 1924 (DJ 0013). European Journal of Taxonomy 1024: 1–197 (2025) 152 Chorology-ecology Isognathotermes ugandensis is the easternmost and southernmost species of the genus Isognathotermes (Fig. 49) its geographic distribution is linked with the Victoria basin forest-savanna mosaic, the east Sudanian savanna, the central Zambezian miombo woodlands, and the northern Acacia-Commiphora bushlands and thickets ecoregions. It settles at high altitudes: Williams (1966) mentioned that all his C. ugandensissampleshadbeencollectedbetween1100and2400ma.s.l.Here,weconfirmandextend this range to 625–2500 m with a range of four subspecies. Molecular data Of the four considered subspecies, only two (I. ugandensis burundii subsp. nov., and I. u. kenyae subsp. nov.) were successfully sequenced. Six mitogenomes of I. ugandensis are published alongside this work (GenBank accessions: see Supp.file3 and ‘Material examined’). Overall, mitogenomes exhibited less than 1.3% dissimilarity with each other (see Supp.file4), with I. u. kenyae (DJ 0599) being the most dissimilar. Our phylogenetic reconstructions placed I. ugandensis+I. minitabundus as sister to I.finitimus (Fig. 33; SHalrt /UFB = 99.3/93), with whom they are less than 2% dissimilar. Of note, I. ugandensis and I. minitabundus exhibit a fungifaber EVA which is distinctive from I.finitimus. Remarks The subdivision of I. ugandensisintofoursubspeciesandthedifficultyofincorporatingI. antennalis into one of these subspecies betrays the vagueness that surrounds the Isognathotermes of East Africa. The morphological diversity of the imagines may result from genuine genetic differences, in which case the subspeciescouldbecomespecies,butitcouldalsoreflectphenotypicplasticitylinkedtoaltitude:only further molecular studies could resolve this question. Isognathotermes ugandensis ugandensis Josens & Deligne subsp. nov. urn:lsid:zoobank.org:act:DDDE8D67-9E45-45F6-952D-EB3CF0D2EA71 Figs 65–69 Diagnosis Soldiers and workers do not allow this subspecies to be distinguished from the other three. The imago is close to that of I. u. burundii subsp. nov.; it is, on average, the smallest of the four subspecies, with, relatively speaking, the widest eyes (“ugug” in Fig. 65, Table 17). Isognathotermes u. ugandensis is also the subspecies that comes from the lowest average altitude (625– 1500 m, average = 1015 m); the samples come from Uganda, South Sudan, eastern CAR and Haut-Uele province, DRC). To date, no samples have been sequenced. Etymology The name refers to the country (Uganda) of the type locality. Material examined Sixty one old samples from 28 locations. Of the 61 old museum samples examined, 20 were initially labelled as Cubitermes ugandensis, 18 as C. antennalis,fiveasC. speciosus, and 18 as Cubitermes sp. Syntypes of Cubitermes ugandensis Fuller, 1923 = type of Isognathotermes ugandensis ugandensis subsp. nov. UGANDA•soldier,worker;nearEntebbe?;2°0′N,33°0′E;1921;H.L.Dukeleg.;studycode:DJ0289; initially C. ugandensis; AMNH. JOSENS G. et al., Isognathotermes (Termitidae: Cubitermitinae) integrative revision 153 Syntypes of Cubitermes antennalis Sjöstedt, 1924 DEMOCRATICREPUBLICOFTHECONGO•soldier,worker,♀(alate),♀(queen);Moto;2°54.47′N, 29°24.85′E;1923;L.Burgeonleg.;studycode:DJ0013;initiallyC. antennalis in RMCA; BE RMCA Fig. 69. Subspecies of Isognathotermes ugandensis (Fuller, 1923) imagines. A. Dorsal and lateral views of an alate female’s head capsule from a colony of I. ugandensis burundii ssp. nov. (DJ 0368). B. Same views of an alate male’s head capsule from a colony of I. ugandensis kenyae ssp. nov. (DJ 0669). C. Same views of an alate female’s head capsule from a colony of I. ugandensis malawii ssp. nov. (DJ 0668). D. Same views of an alate male’s head capsule from a colony of I. ugandensis ugandensis ssp. nov. (DJ 0570). The vertical lines show that the kenyae subspecies is larger and ugandensis smaller. Note the relative size of the eyes, which is smaller in the burundii and larger in the ugandensis subspecies.