Out of sight, out of mind? Ixalidiidae, a new family of African forest grasshoppers (Orthoptera, Acridoidea) revealed by molecular phylogenetics and genital morphology

Directeur De la publication / Publication director : Gilles Bloch Président du Muséum national d’Histoire naturelle réDactrice en chef / editor-in-chief : Laure Desutter-Grandcolas assistante De réDaction / assistant editor : Anne Mabille ([email protected]) Mise en page / Page layout : Anne Mabille coMité scientifique / scientific board : Nesrine Akkari (Naturhistorisches Museum, Vienne, Autriche) Maria Marta Cigliano (Museo de La Plata, La Plata, Argentine) Serge Gofas (Universidad de Málaga, Málaga, Espagne) Sylvain Hugel (CNRS, Université de Strasbourg, France) Marco Isaia (Università degli Studi di Torino, Turin, Italie) Rafael Marquez (CSIC, Madrid, Espagne) Jose Christopher E. Mendoza (Lee Kong Chian Natural History Museum, Singapour) Annemarie Ohler (MNHN, Paris, France) Jean-Yves Rasplus (INRA, Montferrier-sur-Lez, France) Wanda M. Weiner (Polish Academy of Sciences, Cracovie, Pologne) couverture / cover : Unusually colored female of Ixalidium haematoscelis from the Taita Hills, Kenya, with yellow markings instead of the typical uniform brownish coloration. 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Diffusion – Publications scientifiques Muséum national d’Histoire naturelle CP 41 – 57 rue Cuvier F-75231 Paris cedex 05 (France) Tél. : 33 (0)1 40 79 48 05 / Fax : 33 (0)1 40 79 38 40 [email protected] / https://sciencepress.mnhn.fr © Publications scientifiques du Muséum national d’Histoire naturelle, Paris, 2025 ISSN (imprimé / print) : 1280-9551/ ISSN (électronique / electronic) : 1638-9387 489 ZOOSYSTEMA • 2025 • 47 (24) © Publications scientifiques du Muséum national d’Histoire naturelle, Paris. www.zoosystema.com Claudia HEMP University of Bayreuth, Department of Plant Systematics Universitaetsstr 30, 95447 Bayreuth (Germany) and Helmholtz Centre for Environmental Research (UFZ) Permoserstraße 15, 04318 Leipzig (Germany) [email protected] J. Mark RITCHIE The Natural History Museum, Cromwell Road, London SW7 5BD (Great Britain) [email protected] Maria Marta CIGLIANO Museo de La Plata, CEPAVE-CONICET – UNLP, Paseo del Bosque 1900, La Plata (Argentina) [email protected] Klaus-Gerhard HELLER Triesdorf Bahnhof 8, 91732 Merkendorf (Germany) heller[email protected] Elżbieta WARCHALOWSKA-ŚLIWA Beata GRZYWACZ Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Sławkowska 17, 31-016 Kraków (Poland) [email protected].pl; [email protected] Jackson LINDE Department of Entomology, Texas A&M University, College Station, TX (United States) [email protected] Onur ULUAR Department of Biology, Faculty of Science, Akdeniz University, 07058 Konyaaltı/Antalya (Turkey) [email protected] Charly OUMAROU NGOUTE Laboratory of Zoology, Faculty of Science, University of Douala, Laboratory of Zoology, Faculty of Science, University of Douala (Cameroon) [email protected] Hojun SONG Department of Entomology, Texas A&M University, College Station, TX (United States) [email protected] Submitted on 4 August 2024 | Accepted on 26 March 2025 | Published on 3 October 2025 Out of sight, out of mind? Ixalidiidae, a new family of African forest grasshoppers (Orthoptera, Acridoidea) revealed by molecular phylogenetics and genital morphology 490 ZOOSYSTEMA • 2025 • 47 (24) © Publications scientifiques du Muséum national d’Histoire naturelle, Paris. www.zoosystema.com urn:lsid:zoobank.org:pub:C09919D9-3256-4F31-AED4-C7A36A06326C Hemp C., Ritchie J. M., Cigliano M. M., Heller K.-G., Warchalowska-Śliwa E., Grzywacz B., Linde J., Uluar O., Oumarou Ngoute C. & Song H. 2025. — Out of sight, out of mind? Ixalidiidae, a new family of African forest grasshoppers (Orthoptera, Acridoidea) revealed by molecular phylogenetics and genital morphology. Zoosystema 47 (24): 489-553. https://doi.org/10.5252/zoosystema2025v47a24. http://zoosystema.com/47/24 ABSTRACT This paper presents the most comprehensive higher level phylogeny of the Acridomorpha to date, based on molecular data, clearly showing that the genera Mazaea Stål, 1876, Ixalidium Gerstäcker, 1869, Tangana Ramme, 1929 and Rowellacris Ritchie& Hemp n.gen., previously assigned to the Acrididae, belong to a single clade, constituting a previously unsuspected monophyletic family-level group that we are naming Ixalidiidae Hemp, Song& Ritchie n. fam. This paper combines molecular phylogenetics, morphotaxonomy, cytogenetics and bioacoustics to characterize this new family, and presents a comprehensive character tableas context for its placement within the Acridoidea. The family Ixalidiidae Hemp, Song& Ritchie n. fam. currently comprises five genera, two from West and Central Africa: Mazaea and Barombia Karsch, 1891 and three from the montane and coastal forests of Tanzania and Kenya: Ixalidium, Tangana and Rowellacris Ritchie& Hemp n.gen. Three species originally described in Ixalidium are transferred to Rowellacris Ritchie& Hemp n.gen.: R.usambarica (Ramme, 1929) n.comb. (as type species), R.transiens (Ramme, 1929) n. comb. and R.obscuripes (Miller, 1929) n. comb. R.usambarica and R.obscuripes are recalled from synonymy under Ixalidium haematoscelis Gerstäcker, 1869. The monotypic genus Eubocoana Sjöstedt, 1931 is synonymised with Mazaea and the previously unknown male of Mazaea tristis (Sjostedt, 1931) n. comb. is described. Lectotypes are designated for Barombia tuberculosa Karsch, 1891 and for Ixalidium haematoscelis Gerstäcker, 1869. The paper describes the diverse and unusual morphology of the male and female genitalia and documents the exceptional chromosome number of Ixalidiidae Hemp, Song& Ritchie n. fam. and the drumming behaviour of Rowellacris Ritchie& Hemp n.gen. and Tangana. An unexpected sister-group relationship between the African Ixalidiidae Hemp, Song& Ritchie n. fam. and the South American Tristiridae revealed by the molecular phylogeny points to the existence of a common ancestor in Western Gondwana (Atlantica), predating the final separation of South America and Africa around the beginning of the late Cretaceous period 100million years ago. RÉSUMÉ Loin des yeux, loin du cœur ? Ixalidiidae, une nouvelle famille des acridiens forestiers africains (Orthoptera, Acridoidea) révélée par la phylogénie moléculaire et la morphologie des genitalia. Cet article présente la phylogénie de niveau supérieur la plus complète à ce jour des Acridomorpha, basée sur des données moléculaires, montrant clairement que les genres Mazaea Stål, 1876, Ixalidium Gerstäcker, 1869, Tangana Ramme, 1929 et Rowellacris Ritchie & Hemp n.gen., précédemment attribués aux Acrididae, appartiennent à un seul clade, constituant une famille monophylétique, jusqu’alors insoupçonnée, que nous nommons Ixalidiidae Hemp, Song & Ritchie n.fam. Cet article combine la phylogénie moléculaire, la morphotaxonomie, la cytogénétique et la bioacoustique pour caractériser cette nouvelle famille, et présente une tablede caractères complète comme contexte pour son placement au sein des Acridoidea. La famille des Ixalidiidae Hemp, Song& Ritchie n.fam. comprend actuellement cinq genres, deux d’Afrique occidentale et centrale : Mazaea et Barombia Karsch, 1891 et trois des forêts d’altitude et côtières de Tanzanie et du Kenya : I xalidium, Tangana et Rowellacris Ritchie & Hemp n.gen. Trois espèces initialement décrites dans Ixalidium sont transférées dans Rowellacris Ritchie & Hemp n.gen. : R.usambarica (Ramme, 1929) n.comb. (comme espèce type), R.transiens (Ramme, 1929) n. comb. et R. obscuripes (Miller, 1929) n. comb., R.usambarica et R.obscuripes sont rappelés de la synonymie sous Ixalidium haematoscelis Gerstäcker, 1869. Le genre monotypique Eubocoana Sjöstedt, 1931 est mis en synonymie avec Mazaea et le mâle précédemment inconnu de Mazaea tristis (Sjöstedt, 1931) n.comb. est décrit. Des lectotypes sont désignés pour Barombia tuberculosa Karsch, 1891 et pour Ixalidium haematoscelis Gerstäcker, 1869. L’article décrit la morphologie diversifiée et inhabituelle des genitalia mâles et femelles et documente le nombre exceptionnel de chromosomes des Ixalidiidae Hemp, Song& Ritchie n. fam. et la communication par tambourinage chez Rowellacris Ritchie & Hemp n. gen et Tangana. Une relation de groupe frère inattendue entre les Ixalidiidae Hemp, Song& Ritchie n. fam. africains et les Tristiridae sud-américains révélée par la phylogénie moléculaire montre l’existence d’un ancêtre commun dans l’ouest du Gondwana (Atlantica), antérieur à la séparation définitive de l’Amérique du Sud et de l’Afrique, vers le début de la fin du Crétacé, il y a 100millions d’années. MOTS CLÉS Acridoidea, phylogénie moléculaire, phylogénie, Ixalidium, Tangana, Montagnes de l’Arc Est Africain, Crétacé, genre nouveau, famille nouvelle. KEY WORDS Acridoidea, molecular phylogenetics, phylogeny, Tangana, Eastern Arc Mountains, Cretaceous, new genus, new family. 491 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) INTRODUCTION The Acridoidea MacLeay, 1821 is the largest superfamily within Caelifera Ander, 1936, containing over 8 400 described species of grasshoppers defined by distinctive male phallic complex morphology and other traits (Roberts 1941; Amédégnato 1974; Kevan 1982; Song& Mariño-Pérez 2013). According to the Orthoptera Species File (Cigliano etal. 2024), Acridoidea includes ten families, of which the Acrididae Ander, 1936 are by far the largest, exceeding 6 800 species (Song etal. 2018). The phylogenetic relationships among these families are mostly well-understood from molecular phylogenetic studies (Leavitt etal. 2013; Song etal. 2015, 2020), although the positions of Dericorythidae Jacobson& Bianchi, 1905 and Lathiceridae Dirsh, 1954have not been tested due to a lack of molecular-grade specimens. Previous studies consistently found Acridoidea to be monophyletic and sister to Pyrgomorphoidea Brunner von Wattenwyl, 1874, with a clade consisting of Pamphagodidae Bolívar, 1884 and Pamphagidae Burmeister, 1840 hypothesized as the earliest diverging lineage. The taxonomy of the genus Ixalidium Gerstäcker, 1869has historically been problematic, with incorrect synonymies and misidentifications complicating its classification (Uvarov 1941; Dirsh 1966). Its assignment to various subfamilies within Acrididae, based on dubious external characters and single genital characters, has added to the confusion. What we now know to be the related West African genera (Mazaea Stål, 1876, Barombia Karsch, 1891 and the former Eubocoana Sjöstedt, 1931) have also been understudied. However, recent molecular phylogenetic studies supported by genital morphology have clarified the phylogeny of Ixalidium and its allies. Grasshoppers, including several Ixalidium species, serve as important bioindicators and are critically impacted by environmental degradation (Jago in Rowell etal. 2015; Oumarou Ngoute etal. 2020). Some Ixalidium species are listed among globally threatened insects in the Eastern Arc Mountains and Coastal Forests (EACF) of Kenya and Tanzania (Gereau etal. 2016). The current study builds on research and field collecting by the UK Natural Resources Institute (NRI) from 1980 to 1996, and collecting and ecological studies by CH in the forests of Mt Kilimanjaro and the Eastern Arc Mountains of Tanzania. This research has amassed extensive collections of Ixalidium, whose identification was challenging due to their nymph-like and conserved external morphology. Molecular techniques have been used to elucidate species boundaries and phylogenetic relationships. Collaboration between CH and HS, along with earlier unpublished morpho-taxonomic work by MR at NRI, have significantly advanced this study. This paper presents a comprehensive higher-level phylogeny of the Acridomorpha, confirming that the genera Mazaea, Ixalidium, Tangana, and Rowellacris Ritchie& Hemp n.gen. form a monophyletic family-level group, here named Ixalidiidae Hemp, Song& Ritchie n.fam., to which the genus Barombia Karsch is added on morphological grounds. This is the first new family group within Caelifera to be based primarily on molecular phylogenetic evidence, supported by morphological data. Material from various collections, including newly collected DNA samples from Tanzania, was examined, and representatives were dissected and imaged to facilitate comparisons and characterizations. The study provides means to accurately distinguish included genera and previously described species and reveals previously unrecognized diversity within the group. To contextualize the new family morphologically among other extant families, an extensive literature review was conducted to develop a character tablefor Acridoidea, showing the congruence of 24morphological characters across Ixalidiidae Hemp, Song& Ritchie n.fam. and nine other acridoid families. The paper defines these characters, assesses their consistency within families, and highlights the unique combination of characters that define Ixalidiidae Hemp, Song& Ritchie n.fam. The phylogenetic tree also suggests a previously unsuspected sister relationship between Ixalidiidae Hemp, Song& Ritchie n.fam. and the South American fam - ily Tristiridae Rehn, 1906, though with low support value, indicating potential evolutionary significance. MATERIAL AND METHODS Molecular analyses Taxon sampling To reconstruct the phylogeny of Acridomorpha and to place Ixalidiidae Hemp, Song& Ritchie n.fam. in the phylogeny, we compiled taxon sampling that included representatives of all major families within the Acridomorpha, except Lathiceridae, for which we did not have access to DNA-grade specimens. We included representatives of the superfamilies Tanaoceroidea Rehn, 1948, Trigonopterygoidea Walker, 1870, Pneumoroidea Thunberg, 1810, Pyrgomorphoidea Brunner von Wattenwyl, 1874, and Acridoidea. Specifically for Acridoidea, we included 22species of Acrididae, one species of Dericorythidae, six species of Ixalidiidae Hemp, Song& Ritchie n.fam., six species of Lentulidae Dirsh, 1956, five species of Ommexechidae Bolívar, 1884, five species of Pamphagidae, one species of Pamphagodidae, one species of Pyrgacrididae, three species of Romaleidae, and nine species of Tristiridae. Of the 75 species included in the analyses, sequence data for 26 species were generated for this study. Detailed information about taxon sampling is found in Appendix 1. Sequence data generation We sampled complete mitochondrial genomes, 18S rRNA, and 28S rRNA for character sampling. To generate the sequence data, four different methods were used. For four species of Tristiridae (Atacamacris diminuta Carbonell& Mesa, 1972, Punacris peruviana (Saussure, 1888), Circacris auris Ronderos& Cigliano, 1989 and Eremopachys bergii Brancsik, 1901), we performed shotgun sequencing of genomic DNA using the Illumina platform. Mitochondrial genomes and rRNA sequences were assembled as described in Song etal. (2018). For Hoplolopha asina (Saussure, 1887) and Chromacris trogon (Gerstäcker, 1873), we generated de novo transcriptomes and 492 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. mitochondrial genome data were assembled using the methods described in Shin etal. (2024). For Bacteracris sp., Usambilla sagonai (Ramme, 1929), Zulutettix tarranti Otte& Armstrong, 2017 and Bullacris membracioides (Walker, 1870), we used non-target bycatch sequences obtained while capturing loci using the Orthoptera-specific Target Enrichment according to the method described in Shin etal. (2024). The mitochondrial and rRNA genes were obtained using Geneious Prime using sequences of closely related species as references. The sequence data for these seven species were generated as part of previous studies but have not been published yet. For six Ixalidiidae Hemp, Song& Ritchie n.fam. species, three species of Ommexechidae (Aucacris bullocki Rehn, 1943, Spathalium audouinii (Blanchard, 1836), Tetrixocephalus willemsei Gurney& Liebermann, 1963), two species of Tristiridae (Elasmoderus lutescens (Blanchard, 1851), Peplacris rucutita Rehn, 1942), and two species of the acridid subfamily Catantopinae Brunner von Wattenwyl, 1893 (Coenona brevipedalis Karsch, 1896, Serpusia opacula Karsch, 1891), we generated sequence data de novo using shotgun sequencing. To extract high molecular weight DNA required for Illumina sequencing, we used a MasterPure™ Complete DNA and RNA Purification Kit (LGC Biosearch Technologies, London, U.K.) following the manufacturer’s guidelines. The quality and concentration of DNA extracts were initially measured using a Qubit Fluorometer (Thermo Fisher, Waltham, MA, U.S.A.). Shortinserts of 350 bp paired-end libraries were prepared for all samples using NEBNext® Ultra™ II FS DNA Library Prep Kit for Illumina® (Biolabs) and 6 PCR cycles. Size-selection and clean-up was applied using SPRI beads and the library was subsequently checked using a Tapestation DNA screentape and D1000 reagents kit (Agilent). All paired-end libraries were shotgun sequenced on one lane of Illumina HiSeq 4000 at Novogene Inc. in paired-end 150 cycle mode. For these 13 newly generated sequences, the complete mitochondrial genomes were obtained from raw shotgun sequences using the organelle genome assembly toolkit GetOrganelle v1.7.7.0 (Jin etal. 2020). The assembly of the mitogenomes were executed with the following commands: -F animal_mt, -R 10 and -k 21,45,65,85,105. Subsequently, the obtained mitochondrial genomes were submitted to MITOS2 webserver (http://mitos2. bioinf.uni-leipzig.de/index.py) (Donath etal. 2019) for annotation (reference: RefSeq 63). The annotated genomes were manually checked and adjusted via Geneious Prime®2022.1.1 (https://www.geneious.com) to ensure the accuracy. The 18S and 28S rRNA genes were obtained using Geneious Prime and closely related Lentula callani reference sequences for each gene respectively; KM853234.1, KM853456.1 and KM853632.1 (Song etal. 2015). Phylogenetic analysis For mitochondrial protein-coding genes, we aligned based on the conservation of reading frames by first translating into amino acids (using invertebrate mitochondrial genetic code) and aligning individually in MUSCLE (Edgar 2004) using default parameters in Geneious Prime (Dotmatics). For mitochondrial ribosomal RNA genes (16S and 12S) and nuclear ribosomal RNA genes (18S and 28S), each gene was individually aligned using MAFFT (Katoh& Standley 2013) using the E-INS-I option also in Geneious Prime. These individual alignments were concatenated into a single total evidence matrix using SequenceMatrix (Vaidya etal. 2011). We partitioned the data into 17 data blocks (13mitochondrial protein-coding genes, 2mitochondrial rRNAs and 2 nuclear rRNAs). We used IQ-TREE (Minh etal. 2020) to select a best-fit model for each partition, reconstruct the maximum likelihood (ML) tree, and assess branch supports using the ultrafast bootstrap (1 000 replications). Tanaocerus koebelei Bruner, 1906 (Tanaoceridae) was used to root the tree. Divergence time estimation Because there is no reliable fossil available for most lineages within Acridoidea, we opted to use the divergence time estimates from Song etal. (2018) and Song etal. (2020) as calibration points. We used five calibration points: (1) 48.56 to 75.15mya for the common ancestor of Acrididae; (2) 127.88 to 189.44mya for the common ancestor of Pamphagodidae and Pamphagidae; (3) 182.26 to 229.53mya for the common ancestor of Acridoidea; (4) 89.37 to 133.66mya for the common ancestor of Pyrgomorphidae Brunner von Wattenwyl, 1874; and (5) 222.46 to 277.86mya for the common ancestor of all included taxa except Tanaoceridae. We performed divergence time analyses of the unpartitioned dataset using MCMCTree implemented in the software package PAML v4.9130 (Yang 2007). We set the model HKY85+G with fiverate categories and set the root age as 298.97mya. We conducted Hessian matrix calculations according to the above specifications with CODEML as implemented in PAML. MCMC chains ran for 100 000 generations (sfreq = 100) while discarding a burn-in of 25 000 generations. A total of two independent runs were done at using Texas A&M High Performance Research Computing. The effective sample size was checked with the Tracer v1.7.1131 (ESS > 200). Morphology Descriptions, dissection and imaging Where descriptions have been provided for monotypic genera, these reflect the characters and character states visible in the material examined that have been attributed to the single described species. However, this material may include as yet unrecognised closely-related species, such that some characters may later prove to be species-specific, rather than generic, if further study reveals unrecognised speciation. Where possible measurements have been taken from viable samples from a limited area, named in the relevant tablecaptions. Length of fastigium of vertex is measured from its apex to it base, which is considered to be a line constituting the shortest distance between the eyes (Dirsh 1965: 5). Male genitalia were extracted and prepared for study using the method of Dirsh (1956). After removal of genitalia, compressed macerated paper tissue was substituted within the abdominal cavity so that the terminalia retained their natural position after drying. Female genitalia of representative species were dissected and prepared for study by the 493 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) method described by Slifer (1940). The entire abdomen was removed at its junction with the metathorax after relaxing the specimen, then macerated in warm NaOH or KOH. Soft tissues were removed and the ovipositor and subgenital plate, together with any attached internal sclerotized structures, were separated from the other abdominal tergites and sternites, washed in distilled water and preserved in 75% ethanol. For digital imaging genitalia preparations were positioned in hand sanitizer gel beneath a layer of 75% ethanol in a glass cavity block. Subgenital plates were slightly flattened for imaging and drawing by placing pieces of glass coverslip over them. Image stacks were obtained with a Zeiss AxioZoom V.16microscope and AxioCam HRc digital camera running Zen software. Stacked images were combined using Helicon Focus software and cleaned using Photoshop Elements 15. Drawings were made using a Wild M5Apo stereomicroscope with a drawing tube at approximately 30× magnification, then scanned, edited and assembled into plates using Photoshop Elements. Cut surfaces, when seen in side view are shown as a jagged line and when seen face-on are shown cross-hatched. Genitalia were stored in an 85% solution of 75% ethanol and 15% propylene glycol in polythene vials pinned with the respective insect specimens. Relevance of acridoid genital morphology for phylogeny The Acridoidea are the largest superfamily of Acridomorpha, and indeed of Caelifera, currently comprising 10 families (Acrididae, Dericorythidae, Lathiceridae, Lentulidae, Ommexechidae, Pamphagidae, Pamphagodidae, Pyrgacrididae, Romaleidae, and Tristiridae) with c.8 400 valid species, of which more than 6800 are currently classified as Acrididae (Cigliano etal. 2023). Roberts (1941), Dirsh (1956), and Amédégnato (1976, 1977) perceived genital morphology as the key to elucidating phylogeny, driven by an underlying evolutionary model that structures become more complex over time. Roberts (1941) and Dirsh (1956) considered genitalia to be unaffected by environmental selection pressures and therefore likely to show ancient patterns of relationship more clearly than external morphology. This view is also implicit in the classification based on genital structures proposed by Eades (2000). However, the presumed reliability of genital morphology as a guide for phylogenetic reconstruction has been questioned in recent studies that show rapid genital differentiation in response to sexual selection pressures (e.g. Song& Bucheli 2010). A molecular phylogeny of the Pyrgomorphidae (Zahid etal. 2021) demonstrated widespread paraphyly among the tribes of both subfamilies based on morphology, owing to convergences both in external shape and in genitalic characters. This highlights the need for extensive taxon sampling and a large amount of molecular data to identify the most phylogenetically informative morphological traits. However, in both crickets and grasshoppers genitalic divergence has been shown to lead to speciation through creating reproductive isolation, either alone (Knowles etal. 2016; Huang etal. 2020), or in combination with ecological selection and isolation (Oneal& Knowles 2013). In the Melanoplus scudderi complex, Huang etal. (2020) found that “distinct male genitalic shapes correspond to independently evolving lineages identified by the genomic data”, confirming the validity of utilizing variation in genitalic shape to delimit recently diverged evolutionary entities. Song& Mariño-Pérez (2013) re-evaluated the taxonomic utility of characters of the male phallic complex across the higher-level classification of Acridomorpha in a phylogenetic framework provided by mitochondrial genomic data (Leavitt etal. 2013). Noting the difficulty of interpreting published images and incomplete or vague descriptions they augmented selective desk study of the synoptic literature on inter-family variation with their own dissections of single species representatives of 13 families of Acridomorpha to generate a character matrix, coding only the 26 characters that they considered were uniformly present in all members of a family (Song& Mariño-Pérez 2013: 246, Table3). They then generated one phylogenetic tree using only the male genitalia characters and a second tree mapping/optimizing this morphological character information onto a family-level phylogenetic analysis of Acridomorpha derived from mitochondrial genome sequence data (Leavitt etal. 2013). Both trees generated by Song& Mariño-Pérez (2013) found the Acridoidea to be monophyletic, but they differed on the relationships among the included families. However, optimization of genitalic morphological characters onto the molecular phylogenetic tree revealed four uncontroverted synapomorphies, that define the branching of the acridoid family tree. These were the possession of epiphallic lophi, a sclerotised epiphallus, presence of the zygoma and presence of a gonopore. Song& Mariño-Pérez (2013) concluded that despite frequent homoplasies occasioned by sexual selection, many male genitalia characters have strong phylogenetic signal and are informative in inferring relationships at and above family level. This is because male genitalia are a composite character suite. Some parts may evolve rapidly (shape of aedeagus for example) and thus be informative at species level (Huang etal. 2020), while other parts may be conserved across phylogeny. Thus, the utility of genitalic characters may vary across different taxonomic levels and groups. Terminology and abbreviations of male genitalia The terminology of the acridoid genitalia used here follows, in some cases with modification, a number of sources, including Snodgrass (1935), Roberts (1941), Dirsh (1956), Amédégnato (1976, 1977) and Eades (1961, 1962, 2000). Many of these terms were defined by Song& Mariño-Pérez (2013) and extensively illustrated for Melanoplus rotundipennis (Scudder, 1878) by Woller& Song (2017). abbreviations Male genitalia Ac arch of cingulum; Ae apodemes of endophallus; As apical sclerites of endophallus; Av valves of aedeagus; B bridge of epiphallus; Ca apodemes of cingulum; Cr rami of cingulum; 494 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Cut incision made during dissection of genitalia; Df dorsal fold (basal fold); Dll dorso-lateral lobes of endophallus (in Tangana); Ead dorsal epiphallic apodeme; Eav ventral epiphallic apodeme; Ef flanges of endophallic apodemes; Ejd ejaculatory duct; Ejs ejaculatory sac; Fu furcula; Lo lophi of epiphallus; Lp lateral plates of epiphallus; Ls lateral spur of cingular apodemes; Lsc lateral sclerite of epiphallus; Ms medial sclerites of endophallus; Pa pallium; Pp paraproct; Sdl sub-dorsal lobe of cingulum; Sh sheath of aedeagus; Sps spermatophore sac; Vl ventral lobe of ectophallus; Vla ventral lobe apodeme; Zyg Zygoma of cingulum. Repositories Coll. AH A. Hochkirch collection, Bremen; Coll. CH C. Hemp collection, Bayreuth; Coll. CHR C.H. Rowell collection, Ayer; MfN, Berlin Museum für Naturkunde (MfN), Berlin; MNHN Muséum national d’Histoire naturelle, Paris; NHMUK Natural History Museum, London; NR, Stockholm Naturhistoriska Rijksmuseum, Stockholm; SMNK Staatliches Museum für Naturkunde, Karlsruhe. bioacoustics To investigate acoustic and vibrational communication, both male and female specimens of selected species (Rowellacris obscuripes n. comb. (Kwale Island near Tanga), R.usambarica n. comb. (Ndelemai Forest Reserve), Rowellacris Ritchie& Hemp n.gen. sp. (Sigi, East Usambara), Tangana asymmetrica (Kimboza Forest Reserve, Morogoro), Tangana sp. (Tanza - nian coast and Zanzibar) were subjected to video recording. Subsequently, the sound was extracted from the video recordings, and the audio data were further processed using Amadeus II and Amadeus Pro software developed by Martin Hairer (http://www.hairersoft.com). Oscillograms depicting the acoustic characteristics of the songs were generated using Turbolab, a software tool from Bressner Technology, Germany. The impact period refers to the time measured from the initiation of one impact to the beginning of the subsequent one, with its reciprocal value denoted as impact repetition rate (IRR). Temperature was measured after each recording, ranging from 22 to 27°C. cytogenetics The study involved cytogenetic analyses of several species, namely, four males of Ixalidium sjostedti from different elevations of Mt Kilimanjaro, the submontane zone at 1430m a.s.l. (HE216, HE222) and lowland forest remnants at the Sugar Cane Plantations (TPC), (HE223, HE224), three males of an undescribed species of Rowellacris Ritchie& Hemp n.gen. from Sigi, East Usambara Mountains (HE218, HE220, HE221), a male of R.usambarica from Ndelemai Forest Reserve (HE227), and one male (HE247) and one female (HE246) of Tangana asymmetrica from Kimboza, Uluguru Mts. Chromosome preparations were made from males and freshly moulted females by dissecting out the testes and ovaries, incubating them in a hypotonic solution (0.9% sodium citrate), fixing them in ethanol: acetic acid (3: 1), and squashing them on slides in a drop of 45% acetic acid. The cover slips were then removed using the dry ice procedure, and the slides were dehydrated and air-dried. The C-banding technique, as described by Sumner (1972), was used to reveal the constitutive heterochromatin, and the silver staining method (AgNO3) was employed to locate the nucleolar organizer region (NOR) as previously reported (Warchałowska-Śliwa& Maryańska-Nadachowska 1992). Furthermore, fluorescence in situ hybridization (FISH) was performed on four species, namely, I.sjostedti (HE216, HE223), Rowellacris Ritchie& Hemp n.gen. sp. (HE218, HE220, HE221), R.usambaricum (HE 227), and T.asymmetrica (HE247), using 18S ribosomal DNA (rDNA) and telomeric DNA (TTAGG)n probes. The FISH technique was applied as previously described in Grzywacz etal. (2018). The chromosomal localization of rDNA sequences was carried out using a biotin-16-dUTP-labeled probe containing a fragment of orthopteran 18S rDNA (Roche Diagnostics GmbH, Mannheim, Germany). The telomeric (TTAGG)n DNA probes were obtained by PCR in the absence of DNA template. The hybridization signals were detected using avidin-FITC (Invitrogen, Life Technologies INC., Carlsbad, California, USA) and anti-digoxigenin rhodamine (Roche Diagnostics GmbH, Mannheim, Germany). Chromosomes were mounted in ProLong Gold antifade reagent containing DAPI (Invitrogen, Life Technologies INC., Carlsbad, California, USA) and analyzed under a Nikon Eclipse 400microscope fitted with a CCD DS-U1 camera using a set of standard filters and an NIS-Elements BR 3.0 image-analyzing system (Nikon). The images were processed and organized with Adobe Photoshop and Lucia Image 5.0 software. RESULTS Molecular analyses We recovered a topology that is largely congruent with the previous studies, and our analysis robustly recovered Ixalidiidae Hemp, Song& Ritchie n.fam. as a monophyletic group and determined its phylogenetic position within Acridomorpha (Fig.1). In terms of superfamily-level relationships, the earliest diverging lineage within Acridomorpha is Tanaoceridae, the sole member of the superfamily Tanaoceroidea. Its basal position has been shown in all previous studies (Klee etal. 2000; Leavitt etal. 2013; Song etal. 2015, 2020). Then, we recovered a clade consisting of Xyronotidae, Pneumoridae, and Trigonopterygidae as the next diverging lineage. Currently, Xyronotidae and Trigonopterygidae are placed in the superfamily Trigonopterygoidea, but our analysis did not recover Trigonopterygoidea as monophyletic. Song etal. (2020) also did not recover monophyletic 495 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) Trigonopterygoidea. Xyronotidae is endemic to Mexico while Trigonopterygidae is endemic to Southeast Asia, and these two families are morphologically quite distinct from each other. It is likely that future studies including larger taxon sampling may result in reclassification of Trigonopterygoidea. We then recovered a sister relationship between Pyrgomorphoidea and Acridoidea, consistent with previous molecular phylogenetic studies (Leavitt etal. 2013; Song etal. 2015; 2020). Within Acridoidea, we recovered a clade consisting of Pamphagodidae and Pamphagidae as the earliest diverging lineage, consistent with the previous phylogenomic study (Song etal. 2020). Our study recovered the South African endemic family Lentulidae as the next diverging lineage. Otte (2024) recently synonymized Lithidiidae Dirsh, 1961 under Lentulidae, and we also found a member of Lithidiidae (Lithidiopsis carinatus Dirsh, 1956) nested within Lentulidae, consistent with Otte’s reclassification. However, this finding is only based on the placement of a single taxon, and it remains to be seen if this reclassification holds up if additional members of the former Lithidiidae (such as Eneremius Saussure, 1888, Lithidiopsis Dirsh, 1956 and Microtmethis Karny, 1910) are included in the phylogenetic analysis. The phylogenetic position of Pyrgacrididae, which includes one genus with two species endemic to the Reunion Islands and Mauritius, is not clear although most agree that it is near the base of the Acridoidea. Leavitt etal. (2013) found Pyrgacrididae to be sister to Acridoidea (minus Pamphagodidae + Pamphagidae), while Song etal. (2015) found it to be at the base of Acridoidea. Song etal. (2020) found a relationship identical to Leavitt etal. (2013). However, none of these studies found the placement of Pyrgacrididae with a strong nodal support value. In the present study, we recovered a different placement of Pyrgacrididae compared to all previous studies and showed that it diverged after Lentulidae diverged. However, the nodal support value for this placement is again not strong, and we may need additional data to ascertain its phylogenetic position. The family Lathiceridae was not included in this or in earlier studies (Leavitt etal. 2013; Song& Mariño-Pérez 2013; Song etal. 2015, 2020) owing to a lack of molecular data. Thus, the phylogenetic relationship of Lathiceridae to other Acridoidea remains unclear. We included a member of the family Dericorythidae, represented by Dericorys annulata (Fieber, 1853) in this study and found it to be nested deep within Acrididae, closely related to the acridid subfamily Hemiacridinae Dirsh, 1956. Recent studies by Chang etal. (2020) and Zhang etal. (2023) have suggested that the Dericorythidae are paraphyletic and closely allied to the Acrididae. A comprehensive revision of the Dericorythidae incorporating molecular analysis in parallel with genital morphology is needed to resolve this issue. Building on earlier molecular studies (Flook& Rowell 1997; Leavitt etal. 2013; Song etal. 2015) a recent phylogenetic study of the Acridoidea (Song etal. 2018), using mitochondrial and nuclear DNA sequences, resulted in a phylogeny of the Acrididae which placed the family in a monophyletic group with Ommexechidae and Romaleidae, which in turn is sister to the Tristiridae. A more recent phylogeny (Song etal. 2020) using a larger taxon sampling recovered a similar relationship but had Ommexechidae more closely related to Acrididae than to Romaleidae. The enhanced and extended phylogeny presented here (Fig.1) confirms that finding, with the Ixalidiidae Hemp, Song& Ritchie n.fam. recovered unambiguously as a monophyletic sister group of the Tristiridae and the two families together as a sister clade of the combined Ommexechidae, Acrididae, and Romaleidae. taxonoMic treatMent This section provides the following elements: firstly a formal morphological description of the family Ixalidiidae Hemp, Song& Ritchie n.fam., followed by brief remarks and a key to the six genera currently included in the family. It should be noted that while Mazaea, Ixalidium, Rowellacris Ritchie& Hemp n.gen. and Tangana have all been shown to be members of the family based on molecular evidence, Barombia is included in the family because its male and female genitalia and other morphology are almost indistinguishable from those of Mazaea, indicating a very close relationship. Next a description is provided for each of the included genera, including the new genus Rowellacris Ritchie& Hemp n.gen. Where a genus comprises more than one described species the included species are listed and for Rowellacris Ritchie& Hemp n.gen. a diagnosis is provided for each of the previously described species transferred to it from Ixalidium. Family ixalidiidae Hemp, Song& Ritchie n.fam. urn:lsid:zoobank.org:act:6362F1F5-8FB9-4FBF-8C40-1B4C710469FB type genus.— Ixalidium Gerstäcker, 1869. etyMology.— Ixalidiidae Hemp, Song& Ritchie n.fam. takes its name from the root of the oldest genus name in the family, Ixalidium Gerstäcker, 1869, which appears to have been derived from the Greek adjective ἴξαλος meaning “bounding, springing”, combined with the final syllables of the old (and now suppressed) genus name Acridium Schaeffer, 1766. description Small to medium sized grasshoppers (males 16.5-27.6mm; females 23.6-39mm), females more robust. Integument rugose and punctate to tuberculate and granulose, variably setose. Antennae with 17-23 segments, from slightly shorter than to slightly longer than head and pronotum together, basal half excluding scape and pedicel dorso-ventrally compressed, widening somewhat from segment three, widest between 3 and 6, with 8-9 distinctly less compressed and terminal segments filiform. Head width across eyes distinctly less than pronotum length and less than pronotum width at its hind margin; head in lateral view obliquely slanted, with vertex produced and frons in profile sometimes shallowly incurved between antennae; eyes of moderate size, ovoid, narrower above, oblique; fastigium of vertex from above rounded angular, with raised lateral margins, forming an angle less than or equal to 90° (in males), projecting over lateral ocelli and antennal bases; 502 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Coloration (Figs3B, E; 19C, D) Male: General ground colour variable, especially in M. granulosa, light to dark brown with lighter banding and spotting and some darker brown to black areas. Antennae in basal half pale buff dorso-externally with darker speckling, pale buff or pale yellow ventro-internally (sometimes light red in M. granulosa), darkening to black towards tips on dorsal and ventral surfaces. Head light to dark brown, sometimes with darker speckling. Eyes light to dark brown with or without pale horizontal line across upper third, continuing caudad across occiput; second oblique curved pale line sometimes crossing lower third of eye, rising sharply caudad. Dorsum of pronotum showing a range of pattern morphs in M.granulosa, some with dark brown medial longitudinal hour-glass marking framing median carina, alternately constricted and widened in prozona and metazona, bounded laterally by paler longitudinal areas of varying width, externally following inner edges of lateral carinae; others unicolorous lighter or darker brown dorsally, with or without pale buff to light brown longitudinal bands along inner margins of pronotal lateral carinae, continued obliquely downwards on mesoand metathoracic pleurae to episternum above hind coxae; dorsum in M.tristis n. comb. dull speckled mid brown, without pale lateral lines, with tubercles blackish except for pale buff tubercles on hind margin. Lateral lobes from light to dark brown, sometimes lacking clear markings, sometimes with pale oblique blotches in prozona, rising from antero-ventral angle caudad, interrupted by first transverse sulcus. Prosternum pale buff, sometimes with dark grey-brown spotting; mesoand metasternum anterior and lateral margins pale, becoming darker brown or grey-brown medially. Dorsum of meso-and metathoracic tergites mid brown medially (with greenish tinge towards lateral plates in M.tristis n. comb.); triangular epimeron on metathoracic pleura anterior to tympanum with large dark brown or black spot in caudal half. Dorsum of abdominal tergite 1 often with pale tubercles at posterior margin; tergites 1-4mid brown with paired dorsolateral dark transverse dashes on hind margins; tergites 5 and 6 dorso-laterally paler; lateral lobes of tergite 2 with pale upper lateral area and dark shiny patch below; tergites 3-5 laterally with dark brown to blackish shiny areas, normally concealed by widest part of hind femur; tergites 7-10 darker (with olive greenish tinge dorso-laterally in M.tristis n. comb.). Abdominal sternites with lateral margins light brown with darker speckling, with dark brown or grey-brown patches medially, becoming chevrons pointing capitad on sternites 7-8. Cerci dorsally light to mid brown with subapical transverse black band, ventrally black with pale tips. Supra-anal plate mid brown, speckled with darker brown. Paraprocts blackish. Sternite 9 to tip of subgenital plate with continuous or interrupted irregular medial longitudinal dark grey-brown to black band, sometimes obsolescent. Fore and mid legs mid dark grey-brown with lighter and darker speckling. All coxal joints blackish below. Hind femur externally and in upper internal area light to mid brown, with three indistinct oblique darker bands, interrupted in medial area, situated at base, 2/5 from base, and between 3/5 from base and knee; knee lunules dark brown. Hind femur internally with medial area dark brown to black throughout, apart from pale buff area in upper half at base, narrow irregular or incomplete pale transverse band half way from base sometimes reduced to small pale blotch on ventral internal carina and small pale mark just above knee; ventral internal area buff or greyish. Hind tibia dorsal and ventral surfaces buff to grey buff, with smoky blotches dorsally in basal half, becoming more evenly smoky grey brown towards tarsi; external spines and claws smoky buff with black tips, sometimes black at base or all black; internal spines usually darker with black tips or all black. Female Coloration similar to male but less contrasted. Triangular epimeron on metathoracic pleura anterior to tympanum without dark blotch; abdominal tergites 2-4 only with lateral dark brown to black shiny areas. history The genus Mazaea was described by Stål (1876) for his single female specimen of an apterous species that he named M.granulosa on account of the small granular tubercles covering the integument of the thorax and hind legs. Stål evidently did not know the provenance of his type specimen which must have been acquired in West Africa by a visiting European before 1876. Given the known geographical range of the genus and Table 1. — Measurements in mm, Mazaea sp. (E Nigeria and S Cameroon). Antenna length Head width Pronotum length Hind femur Length Hind femur depth Femur length / depth Total body length Vertex length Vertex max width Vertex length / max. width Head + pronotum length (h+pl) Antenna length / h+pl Males n12 13 13 11 11 11 13 13 13 13 13 12 Range 7.08-8.89 3.91-4.67 3.93-5.06 12.43-14.6 3.46-4.04 3.23-3.70 20.29-27.56 1.2-1.54 1.1-1.44 0.94-1.23 6.94-9.14 0.93-1.17 Mean 8.14 4.22 4.39 13.49 3.79 3.57 24.04 1.34 1.23 1.09 7.86 1.05 Females n12 13 13 13 13 13 12 13 13 13 13 12 Range 9.1-11.75 4.38-5.09 5.02-6.5 15.49-19.51 4.13-5.11 3.56-3.97 27.7-38.96 1.47-1.79 0.9-1.31 8.74-11.47 0.91-1.12 Mean 10.05 4.78 5.77 17.28 4.59 3.77 33.21 1.79 1.67 1.07 10.00 1.02 503 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) the fact that there were few European settlements on the coast of the Bight of Biafra at that time, it is likely that the type specimen came from a forested location close to what is now Douala in the littoral region of SW Cameroon. However a provenance from coastal areas of Congo, DR Congo, Gabon or Equatorial Guinea is also possible. A CB Fig. 4. — Male heads, dorsal view; A, Ixalidium haematoscelis, Kenya, Taita Hills (NHM, London); B, Rowellacris usambarica n. comb., paratype, Tanzania, Muafa, West Usambara Mts (MfN, Berlin) DORSA BA000802S03 (http://coll.mfn-berlin.de/u/d87ebc); C, Tangana asymmetrica, paratype, Tanzania, Tanga (MfN, Berlin) (http://coll.mfn-berlin.de/u/a08979). Scale bars: A, 0.5 mm; B, C, 1 mm. AC EF G H DB Fig. 5. — A-H. Male terminalia of Ixalidium spp. (A-C), Rowellacris n. gen. spp. (D-G) and Tangana asymmetrica Ramme, 1929 (H), in dorsal view (apart from D which is in lateral view): A, I. haematoscelis (Taita Hills, Kenya, NHMUK 010594102); B, I. bicoloripes Uvarov, 1941 (holotype, Emali, Kenya, NHMUK 010595041); C, I. sjostedti Kevan, 1950 (holotype, Kilimanjaro, Tanzania, NHMUK 010594124); D, E, R. transiens Ramme, 1929, n. comb. (Usambara Mts, Tanzania, NHMUK 010594275); F, R. obscuripes Miller, 1929, n. comb. (holotype, Msimbazi River, Tanga District, Tanzania, NHMUK; 10594720); G, R. usambarica n. comb. (paratype, Muafa, West Usambara Mts, Tanzania, MFN, Berlin, DORSA BA000802S03); H, T. asymmetrica (paratype, Tanga, Tanzania, MfN, Berlin, (MfN URI http://coll. mfn-berlin.de/u/a08979). NHMUK numbers are barcode numbers for the UK Barcode of Life database https://www.ukbol.org/. Scale bar: 1 mm. 504 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Bolívar (1908:105) described M.granulosa var. cingulata from “Loagna” [sic] (probably Loanga, Congo Republic), but this was synonymised by Kirby (1910) apparently as a cataloguing convenience, since he did not recognise varieties. Dirsh (1966:102) repeated the synonymy. All other published records of Mazaea have been attributed to M.granulosa. Sjöstedt (1931) assigned Mazaea, Barombia and his own Eubocoana to “Acanthini”, an informal grouping possessing an external apical tibial spine, but he considered Ixalidium to belong to the “Anacanthini”, which lacked this spine. Dirsh (1965) also used the presence or absence of this spine to organise his key to the genera of the Catantopinae. Today this character would be perceived as potentially subject to rapid evolution. Hollis (1975: 197) studied the presence or absence of the external apical tibial spine within and between different genera of Oxyinae Brunner von Wattenwyl, 1893. In Thanmoia Ramme, 1931 he noted that it could be present or absent and even show both conditions on the two hind legs of a single individual. reMarks Genomic evidence presented elsewhere in this paper (Fig.1) now suggests that the West African Mazaea is the most basallypositioned subclade of the Ixalidiidae Hemp, Song& Ritchie n.fam., which agrees well with the ancestral character states that it exhibits (e.g. the large ejaculatory and spermatophore sacs, elongated apodemes of cingulum and recurved endophallus), that are shared with the East African Ixalidium. These characters have been lost or greatly modified in the other East African subclades of the family, Tangana and Rowellacris Ritchie& Hemp n.gen. Mazaea is also shown to be a member of the Ixalidiidae Hemp, Song& Ritchie n.fam. on the basis of its general habitus (Fig.3) and especially its genitalia (Fig.6). The external morphological features which distinguish Mazaea from the genus Ixalidium are its strongly granulose integument, more pointed vertex, pointed prosternal tubercle (spathulate in Ixalidium) and the presence (usually) of a small external apical spine on the hind tibia (absent in Ixalidium and other East African members of the family). included species Mazaea granulosa Stål, 1876 Mazaea tristis (Sjöstedt, 1931) n. comb. Mazaea granulosa Stål, 1876 (Figs1; 3B, C, E; 6; 7B-H; 8A, B; 18A, B; 19C, D; 22C; Table1) Mazaea granulosa Stål, 1876: 54. type Material. — Holotype • ♀; “Africa occidentalis”; [no further data] (NR, Stockholm). Material exaMined.— Nigeria • 1 ♂; Eastern Province, 20mls NE of Calabar, [Ekinta] Forest Reserve; [5°01’23”N, 8°28’43”E; 8.I.1961]; N.D. Jago leg.; NHMUK014035468 • 1 ♀; same collection data as for preceding, NHMUK. Cameroon • 1 ♂, 1 ♀; Southern Bakundu Forest Reserve; 4°22’- 4°27’N, 9°16’-9°16’E; 9.IX.1968; J.S. Gartlan leg.; #68015 (♂), #68014 (♀); Coll. CHR • 1 ♂; Lake Tissongo, Douala-Edéa National Park; 3°33’48”N, 9°53’9”E; 28.I.1975; T.E. Rowell leg.; #75025; Coll. CHR • 1 ♂; Dja [Faunal Reserve], 2°49’-3°23’N, 12°25’-13°35’E; 16.VII.1975; T.E. Rowell leg.; leaf litter in forest; #75024; Coll. CHR • 1 ♀ nymph; same collection data as for preceding; #75023; Coll. CHR • 1 ♂; Mt Fébé, nr Yaoundé; 3°54’47.99”N, 11°29’19.56”E; 1-11.VII.1975; N.D. Jago leg.; NHMUK 014035469 • 1 ♂; Yaoundé; 3°50’38.8284”N, 11°30’4.8456”E; 20.XII.1973; G. Popov leg.; NHMUK 014035470 • 1 ♀; same collection data as for preceding; NHMUK 014453740 • 2 ♂; Ongot Forest; c.03°51’N, 11°25’E; VIII.2022; C. Oumarou Ngoute leg.; Coll. CH • 1♂; N Yaoundé, Nkométou II; 4°2’0”N, 11°33’0”E; 3.XI.1975; M.Descamps leg.; Coll. CH • 1 ♀; Edea [Forest Plantation], Mangombe Forest Reserve, 23-24.IX.1975; M. Descamps leg.; Coll. CH • 1 ♂; Ongot Forest; 03°51’57.28”N, 11°21’59.52”E; 887m a.s.l.; 5.XII.2021-20. III.2022; J. Yetchom-Fondjo leg.; SMNK • 1 ♂; Yingui, Deng-Deng National Park; 3°21’22”N, 12°44’37”E; 513m a.s.l.; 12.VI.2022; J. Yetchom-Fondjo leg.; SMNK • 1 ♂, 3 ♀; Yingui, Iboti; 04°27’48”N, 10°27’32”E; 746m a.s.l.; 7.I.2022; J. Yetchom-Fondjo leg.; SMNK • 2 ♂; Yingui, Iboti; but 04°27’47.76”N, 10°27’17.94”E; 7.I.2022; J. Yetchom-Fondjo leg.; SMNK • 1 ♂; Sanaga Maritime, Mouanko; 03°38’23”N, 09°46’37”E; 16.VII.2017; J. Yetchom-Fondjo leg.; SMNK • 1 ♂; Nkam, Solé; 04°36’00”N, 09°48’00”E; 28.II.2017; J. Yetchom-Fondjo leg.; SMNK • 2 ♂; Nkam, Djawara; 4°12’15.66”N, 9°50’16.01”E; 6m a.s.l.; 13.III.2017; J. Yetchom-Fondjo leg.; SMNK • 2 ♂, 1 ♀; locality unknown; X.1938-VIII.1939; H. Jacques-Félix leg.; MNHN. Congo Republic • 1 ♂; Dimonika [Biosphere Reserve]; [4°10’0.13”S,12°25’0.12”E]; 28.V.1972; C. Morin leg.; MNHN • 1 ♂; N’go, [2°28’50.7144”S, 15°45’6.0732”E]; 12.III.1973; J.F. Cornic leg.; MNHN • 1 ♂, 1 ♀; Odzala; [c. 0.8°N, 14.9°E]; 9.XI.1977; S. Kelner-Pillault leg.; MNHN • 2♀; Mossendjo, Vouka [Vouga]; [2°34’08”S, 12°44’44”E]; 500m a.s.l.; 14.XII.1973; J. C. Thibaud leg.; MNHN • 1 ♂; same locality as preceding; 2.XII.1973; J. C. Thibaud leg.; MNHN • 1 ♂; same locality as preceding; 2. II.1974; J. C. Thibaud leg.; MNHN. Central African Republic • 1 ♀ ; La Maboke; [3°49’54”S, 17°50’45”E]; 16.I.1968; P. Teocchi leg.; MNHN • 1 ♀ ; same locality as preceding; 24.IV.1968; P. Teocchi leg.; MNHN • 1 ♂, same locality as preceding; 17.XII.1967; P. Teocchi leg.; MNHN. Gabon • 2 ♂, 2 ♀; Ipassa; [c. 00°28’00”N,12°43’00”E]; 30.IX.1974; A. Mougazi leg.; MNHN • 1 ♂, 1 ♀ ; Between Lastourville and Moanda; [between 0°49’2.71”N, 12°42’29.45”E and 1°34’0”S, 13°12’0”E]; 16.VI.1974; M. Donskoff and J. Le Breton leg.; MNHN. diagnosis.— Integument finely rugose and granulose, lacking larger papillate tubercles. Antennae in both sexes from 0.9 to 1.2 times as long as head and pronotum together. Pronotal shoulders in cross-section angular, with clear lateral carinae composed of granular tubercles forming a distinct angle between dorsum and lateral lobes. Pronotal shoulders widening evenly to hind margin, with acute hind angles. Dorso-medial tubercular areas of thoracic tergites and abdomen weakly raised. Measurements: Table1. distribution Most records of Mazaea granulosa are from forested areas of Cameroon. Mestre & Chiffaud (2009) also reported it from the Republic of Congo (Congo Brazzaville), Equatorial Guinea and DR Congo (Congo Kinshasa, formerly Zaire), but without citing specific localities. However, they did not find any record of Mazaea or Barombia from the Central African Republic or from Gabon. Material of M. granulosa from all these countries has been examined for this study. Dirsh (1966: 103) reported a specimen from Dundo, Angola, close to the border with DR Congo. 505 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) The occurrence of Mazaea granulosa in Nigeria, reported by Dirsh (1965, 1966, 1970) and Johnston (1968), but queried by Mestre& Chiffaud (2009), is based on specimens (collected in the Ekinta Forest Reserve in 1961 by N.D. Jago) in the NHMUK collection. This record is not surprising, given that the forested area of Cross River State, now included within the Eastern half of the Oban Group of Cross River National Park, was originally continuous with the Takamanda Forest Reserve in SW Cameroon which borders Nigeria and the Cross River NP. Mestre& Chiffaud (2009) indicated the importance for present-day distribution of forest species of the extreme dry period at the last glacial maximum (25000 to 15000 years BP), which left just two montane forest refugia in SW Cameroon, the western one extending into SE Nigeria. Despite having been gazetted as a National Park, much of the Cross River forests are now within commercial estate concessions, and large parts of them have been cleared for oil palm production (Offiong 2017). In Cameroon, Mazaea granulosa was found to be the most common grasshopper species in three forested areas (Ongot forest, near Yaoundé; Zamakoe forest, near Mbalmayo; and Ngutadjap forest, near Ebolowa) and was most abundant where deforestation was highest (Oumarou Ngoute etal. 2020). It was found in agroforestry plots, crop fields, forest, and fallows in the SW Region and West Regions, but not in the Centre region (the forest-savannah transition zone) (Christel etal. 2019). reMarks Unfortunately, the female holotype of M.granulosa in the Naturhistoriska Riksmuseet, Stockholm, lacks provenance and is not available for study. However, current investigations of the genitalia (Ritchie, unpublished) and mitochondrial genome (Yetchom-Fondjo, pers. comm.) of material presently assigned to Mazaea granulosa indicate a degree of geographical variation. Hence the specimens studied here and the measurements provided in Table1may ultimately be found to represent more than one closely-related species. Mazaea tristis (Sjöstedt, 1931) n. comb. (Figs3F; 9; Table2) Eubocoana tristis Sjöstedt, 1931: 21-22, Plate 2, Figs7, 7a, 7b. Eubocoana tristis Sjöstedt, 1931 (Dirsh 1965: 308-309, fig.235). t ype Material .— Syntypes. Congo Republic • 2 ♀; Boko - Kinka - la, [c. 4°37’36”S, 14°37’11”E to 4°21’41.00”S, 14°45’51.98”E]; [M.] Lundgren leg.; NRM-ORTH0002426 [Type] and NRMORTH0002427 [Cotype] (NR, Stockholm). Material exaMined.— Congo Republic • 1 ♀; Mossendjo, Vouka [Vouga]; [2°34’08”S, 12°44’44”E]; 500m a.s.l.; 1-6.IX.1973; J.C. Thibaud leg.; MNHN • 1 ♂; same collection data as for preceding; 27.XI.1973; J. C. Thibaud leg.; MNHN • 1 ♂; same collection data as for preceding; 15.II.1975; J. C. Thibaud leg.; dense secondary forest; Coll. CH • 1 ♀; same collection data as for preceding; secondary forest; 13.III.1975; J. C. Thibaud leg.; Coll. CH. • 1 ♀; N’go; [2°28’50.7144”S, 15°45’6.0732”E]; 12.III.1973; J. F. Cornic leg.; MNHN. diagnosis.— Integument coarsely rugose, granulose and pitted, with scattering of larger papillate tubercles. Antennae in female about same length as head and pronotum together; male antennae more than 1.2 times as long as head and pronotum together (based on small available sample). Pronotal shoulders in cross-section rounded, irregular, rugose and pitted, lacking clear lateral carinae. Pronotal shoulders widest in prozona, between transverse sulci, maintaining same width, or narrowing slightly, towards hind margin, with rounded hind angles. Dorso-medial tubercular areas of thoracic tergites and abdomen strongly raised. Measurements: Table2. distribution M.tristis n. comb, was until recently only known from two female syntypes, collected by a Swedish missionary, Manne A B C Fig. 6 . — Mazaea granulosa Stål, 1876: A, male, zygoma and aedeagus with dorsal lobe membrane forming aedeagal plug, dorsal view (Cameroon, Ongot); B, female, head and prosternal tubercle, antero-ventral view (Cameroon, Mangombe); C, female, subgenital plate, cleared, dorsal view (Cameroon, Yaounde). Scale bars: A, 0.2 mm; B, 1 mm; C, 0.5 mm. 506 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Lundgren, based at Musana Mission Station in Boko-Kinkala Subdivision, about 120kms W of Brazzaville, Republic of Congo. Recently further males and females have been examined from Republic of Congo, (Vouka [Vouga] and N’go), together with sympatric specimens of M. granulosa. reMarks Sjöstedt (1931) did not designate a holotype for Eubocoana tristis, so despite being labelled as Type and Cotype, the original specimens in the Naturhistoriska Riksmuseet, Stockholm are syntypes. Sjöstedt (1931: 21) also listed females of Mazaea granulosa collected from the type locality of E.tristis by the same collector. Since the original description of Eubocoana, Mazaea tristis n. comb. has not been mentioned in primary taxonomic literature, featuring only in catalogues and in Dirsh’s African genera of Acridoidea (Dirsh 1965: 308-309). Unfortunately, repeated requests for detailed imagery of the type specimens have received no response. However, descriptions and illustrations based on the female syntypes exist (Sjöstedt 1931: 21; Dirsh 1965: 308-309; Cigliano etal. 2023). The only characters adduced by Dirsh (1965) to separate females of Eubocoana tristis from M. granulosa were the fastigium of vertex shorter than wide in E. tristis rather than longer than wide in M.granulosa, the more rugose and tuberculate integument of E. tristis compared to M.granulosa and the absence of pronotal lateral carinae in E.tristis. The male of Mazaea tristis (Sjöstedt, 1931) n. comb. has not previously been described. However, comparison of the vertex measurements of a sample of M.granulosa (Table1) with the newly studied specimens of M.tristis n. comb. (Table2) indicates that there is no consistent difference in proportions between the two taxa, with length / width varying from around 0.9 to 1.3 in M.granulosa and from around 0.9 to 1.2 in M.tristis n.comb. Other standard metrics for M.tristis n. comb. are mostly well within the range for M.granulosa, apart from antenna length in males. Male antennae (in a sample of two) are more than 1.2 times the length of head and pronotum together in M.tristis n. comb., whereas they are either slightly shorter than, or barely longer than head and pronotum together in M.granulosa. However, the lack of distinct pronotal lateral carinae in Mazaea tristis n. comb. and the more tuberculate and rugose integument are confirmed for both sexes. The male genitalia of M.tristis n. comb. (Fig.9A-F) are indistinguishable from those of M.granulosa, while the female spermatheca shows exactly the same complex structure in both taxa. Based on the original description (Sjöstedt 1931: 21), published illustrations of one of the two female syntypes (Dirsh 1965: 309; Cigliano etal. 2023) and examination and dissection of newly available males and females, the genus Eubocoana Sjöstedt, 1931 is therefore here synonymised with Mazaea. Genus Barombia Karsch, 1891 Barombia Karsch 1891: 180. t ype species . — Barombia tuberculosa Karsch, 1891, by monotypy. Barombia tuberculosa Karsch, 1891 (Figs3A, D; 7A; Table3) Barombia tuberculosa Karsch 1891: 180. Barombia tuberculosa var. sublaevis Bolívar, 1905: 226. Synonymised by Kirby (1910: 386). Barombia nassaui Rehn, 1958: 3-5. Synonymised by Dirsh (1966: 101). type Material. — Holotype of Barombia nassaui. Cameroon • ♂; Ja River, Bitje [=Bitye]; [3°01’00”N, 12°22’00”E]; G.L. Bates leg.; Holotype 5808; ANSP, Philadelphia. Lectotype of Barombia tuberculosa. Cameroon • ♂; Barombi Station; Preuss leg.; DORSA BA 000504S01; MfN, Berlin; here designated. Types (status not confirmed) of Barombia tuberculosa var. sublaevis. Equatorial Guinea • “Biafra”; [Cape San Juan; 1°10’29”N, 9°20’31”E];[VI-XI.1901]; [M.] Martinez de la Escalera leg.; [Sex and status of Type(s) not confirmed, Repository not confirmed]. Material exaMined.— Nigeria • 1 ♂, Cross River State, Calabar, 30kms E on Akansako road; 13.XII.1979; J.C. Reid leg.; NHMUK014453739. Central African Republic • 1 ♀ ; La Maboke; [3°49’54”S, 17°50’45”E]; 12.IV.1968; P. Teocchi leg.; MNHN • 1 ♂; La Maboke; [3°49’54”S, 17°50’45”E]; 10.I.1966; R. Pujol leg.; #42; MNHN. Cameroon • 1 ♂; Koupongo (Edea); [c. 3°48’N, 10°08’E]; 25.XI.1975; M. Descamps leg.; MNHN. [Equatorial Guinea] • 1 ♂; “Congo, Riv. San Benito”; 27.II.1905; L. Guiral leg.; [determined as Barombia tuberculosa by W. Ramme]; MNHN. Congo Republic • 1 ♂; Bassin N’gogo-Sanga, Region d’Ouésso; [c.1°36’38”N,16°03’05”E]; 20.III.1905; J. Gravot leg.; [determined Table 2. — Measurements in mm, Mazaea tristis (Sjöstedt, 1931) n. comb. Congo Republic, Vouka (Vouga) and N’go. Antenna length Head width Pronotum length Hind femur Length Hind femur depth Femur length / depth Total body length Vertex length Vertex max width Vertex length / max. width Head + pronotum length (h+pl) Antenna length / h+pl Males n 2 2 2 2 2 2 2 2 2 2 2 2 Range 9.62-9.82 4.38-4.43 4.33-4.54 13.39-13.64 3.63-3.75 3.64-3.69 22.39-25.61 1.44-1.49 1.23-1.48 1.01-1.17 7.86-7.88 1.22-1.25 Mean 9.72 4.41 4.44 13.52 3.69 3.66 24.00 1.47 1.36 1.09 7.87 1.24 Females n 3 3 3 3 3 3 3 3 3 3 3 3 Range 10.24-10.99 4.4-4.98 5.37-5.70 17.35-18.08 4.48-4.66 3.87-4.01 33.44-34.21 1.6-1.9 1.66-1.82 0.90-1.04 9.91-10.31 1.01-1.09 Mean 10.68 4.72 5.56 17.79 4.54 3.92 33.89 1.71 1.77 0.97 10.12 1.06 507 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) as Barombia tuberculosa by W. Ramme]; MNHN • 1 ♂; [Niari Department], Mossendjo [District], Vouka [Vouga]; [2°34’08”S, 12°44’44”E]; 500m a.s.l.; 1-2.XII.1973; J. C. Thibaud leg.; MNHN • 1 ♀ ; same locality as preceding; 4.II.1974; J. C. Thibaud leg.; MNHN. Gabon • 1 ♂; Fernan Vaz; [0°27’0”S, 10°28’0”E]; 1.I.1990; E.Cherlonneix leg.; MNHN-EO-CAELIF 11142; MNHN • 1 ♂; Cap Estérias; [c. 0°37’0”N, 9°19’60”E]; 15-16.V.1974; M. Donskoff and J. Le Breton; MNHN-EO-CAELIF 11141; MNHN • 1 ♂; Ipassa; [0°28’0”N, 12°43’0”E]; 3-30.V.1974; M. Donskoff and J. Le Breton leg.; quadrat; Coll. CH • 1 ♀; Ipassa; [0°28’0”N, 12°43’0”E]; 450-550m a.s.l.; 28-30.IV.1974; M. Donskoff and J.Le Breton leg.; leopard trail; Coll. CH. redescription Appearance distinctive (Figs3A; 19G, H). Medium size (male, c.23.5-27mm; female c.32-36mm). Integument coarsely rugose, granulose and punctate. Head Antenna filiform, with 23 articles (Dirsh, 1965), about 1.451.6 times (male), 1.3-1.4 times (female) as long as head and pronotum together. Head conical; frons in profile oblique and indented at median ocellus; fastigium of vertex strongly A C D E H F G B Fig. 7. — Barombia Karsch, 1891 and Mazea Stål, 1876 male terminalia and genitalia: A, B, male terminalia, dorsal view; A, Barombia tuberculosa Karsch, 1891 (Nigeria, Cross River State); B, Mazaea granulosa Stål, 1876 (Cameroon, Mt Fébé); C, H, male genitalia, Mazaea granulosa (Nigeria, Cross River State, NHMUK 014035468); C, epiphallus, posterior view; D, same dorsal view; E, aedeagus, posterior view; F, phallic complex, lateral (epiphallus removed); G, same, dorsal (epiphallus in place); H, same, ventral. Scale bars: A, B, F, G, 1 mm; C, D, 0.4 mm; E, 0.2 mm; H, 0.5 mm. 508 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. projecting beyond eyes, horizontal, acutangular, as long as or slightly longer than its basal width, with marginal carinae in apical half but with medial carinula obsolete (Fig.3D). Face and lower genae coarsely rugose and punctate. Frontal ridge medially produced, narrow, bladelike above antennae, becoming shallow with carinulae present between antennae and median ocellus, obsolete ventrally. Head width across eyes c. 2.9-3.5 times length of vertex (males), c.2.6-2.9 times (females) (measured to narrowest point between eyes). Lateral ocelli barely visible from above. Eyes from above protuberant and globular (Fig.3D). Thorax Pronotum short, not covering mesonotum, with deep transverse sulci dividing prozona into anterior and posterior sections and separating prozona from much reduced metazona; prozona about 4.8 times as long as metazona, with both sections having strongly raised and bluntly pointed dorso-medial lobes, of variable development, the posterior lobe somewhat larger; anterior and posterior sections of prozona and metazona with pointed dorso-lateral tubercular lobes, small or obsolescent in anterior section of prozona, but larger in posterior section of prozona and in metazona; metazona not raised but with very small medial pointed lobe; hind margin of metazona medially indented; prosternal process acutely conical. Mesonotum low, with fore margin medially indented, as broad as or broader than pronotum, hind margin ridged and tuberculate. Mesosternal interspace open, longer than its minimum width; mesosternal lobes with smoothly curving posterior margins. Elytra and wings absent. Metanotum and first abdominal tergite inflated (Fig.3A), coarsely granulose, with median carina forming irregular raised arcuate or pointed medial lobes, subtriangular in dorsal view. Abdomen Dorsally carinate. Tympanum large, oval, sclerotised. Supraanal plate divided into basal and apical portions by a transverse furrow, its basal portion narrowly embedded into last abdominal tergite, with broad medial longitudinal groove and with shallowly concave carinate hind margin with papillate flanges at its outer ends (Fig.7A); hinged apical portion shield-shaped, longer than its basal width. Subgenital plate subconical, postero-ventrally slightly concave in lateral view, with acutely conical apex. Cerci elongate conical, with digitate tips, clothed with long setae. Legs Hind femur of moderate depth (c. 3.7-3.9 times as long as maximum depth, male; c. 3.7 times, females), with serrated upper carina, tuberculate upper and lower marginal areas, rounded knee lobes. Hind tibia with 8 inner and 7 outer spines, small external apical spine usually present (as in Mazaea, Fig.3C). Arolium large, diameter less than claw length. Male genitalia Very similar to those of Mazaea in all respects (Fig.7). Female Internal genitalia with spermatheca of similar configuration to that found in Mazaea, with long duct repeatedly looped and coiled in two distinct clusters to left and right sides of abdomen, becoming narrower in its apical section and ending with short vermiform subapical diverticulum and longer looping vermiform apical diverticulum; overall length of spermathecal duct shorter than in Mazaea spp. and with proportionately shorter apical diverticulum. Subgenital plate similar in shape to that in Mazaea species, as described above. Measurements Table3. Coloration (Figs3A; 19G, H) In contrast to other genera of Ixalidiidae Hemp, Song& Ritchie n.fam., ground colour olivaceous green to buff, variegated with light rufous brown markings, with some tubercles yellowish; antennae black with apical segments usually white; abdominal tergites 2-5 laterally with black shiny patches; abdominal sternites 2-7 variably infused with black; hind femora externally yellowish buff in basal half, with dark grey to blackish oblique transverse banding in apical half; black patches in basal half on upper and lower outer areas and internal medial area; ventral internal area brownish to blackish; knee lunules black; tibiae mottled brown and dark grey with spines black-tipped. Table 3. — Measurements in mm, Barombia tuberculosa (Karsch, 1891). E Nigeria, S Cameroon, Congo Republic, Equatorial Guinea, Central African Republic and Gabon. Antenna length Head width Pronotum length Hind femur Length Hind femur depth Femur length / depth Total body length Vertex length Vertex max. width Vertex length / max. width Head + pronotum length (h+pl) Antenna length / h+pl Males n5 9 9 9 9 9 9 9 9 9 9 5 Range 11.29-13.57 4.23-4.67 3.85-5.06 12.79-14.61 3.37-3.87 3.66-3.96 22.7-27.12 1.27-1.5 1.05-1.39 0.99-1.21 7.45-8.85 1.48-1.58 Mean 12.23 4.43 4.40 13.74 3.61 3.81 24.78 1.39 1.24 1.12 8.03 1.54 Females n3 3 3 3 3 3 3 3 3 3 3 3 Range 12.91-13.8 5.05-5.12 4.85-5.68 15.61-18.89 4.18-4.44 3.73-4.25 31.02-35.47 1.72-1.94 1.64-1.73 1.0-1.18 9.37-10.14 1.31-1.39 Mean 13.33 5.09 5.26 17.48 4.34 4.02 33.24 1.82 1.69 1.12 9.81 1.36 509 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) distribution The genus Barombia was described by Karsch (1891: 180) for his species B. tuberculosa collected from Barombi Station, Cameroon, by the botanist Paul Preuss, who also collected material of Mazaea granulosa at the same location (Karsch 1891: 179). Mestre& Chiffaud (2009) suggest that Barombi Station was close to present-day Kumba. The type locality for var. sublaevis Bolívar, 1905, was initially given as“Biafra”. Bolívar omitted to mention any specific locality, or the sex of his type material. However, it was actually from Cape San Juan, as indicated in the catalogue of species from Spanish Guinea (Anonymous 1910: 580). It seems possible that he did not intend to formally designate a type for his record of this variety. The location of Bolívar’s material has not been confirmed, but may be the MNCN, Madrid (Mestre & Chiffaud 2009: 25). Further specimens from Cameroon A D B C Fig. 8. — Female genitalia: A, Mazaea granulosa Stål, 1876, ovipositor valves and spermatheca, duct partially unravelled, ventral view; B, same, apex of spermatheca enlarged; C, Ixalidium sjostedti Kevan, 1950, ovipositor valves and spermatheca, ventral view; D, same, apex of spermatheca, enlarged, dorsal view. Scale bars: A, 2 mm; B, 0.5 mm; C, D, 1 mm. 510 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. were reported from Bibundi (Massa 2020) and from “Bonge” (Bong?) by Sjöstedt (1910). In Cross River State, Nigeria a male was collected from Ekinta Forest Reserve (NHMUK 014453739). Dirsh (1965, 1966, 1970) reported Barombia as present in Congo Republic and Congo Democratic Republic, in addition to Cameroon and Equatorial Guinea. Recently material from Congo Republic and Gabon (Ipassa) has been examined (MNHN). The large protuberant eyes, long antennae and overall greenish coloration of Barombia suggest that it inhabits the field layer rather than the leaf litter where the more sombre Mazaea is normally found. history Karsch (1891: 180) made clear in his description that he considered Barombia and Mazaea closely allied. Dirsh (1965: 302) also demonstrated their close relationship in his key to the Catantopinae and in his drawings of their genitalia (Dirsh 1966, 1970) which clearly showed the supplementary apodemes of cingulum that link these two genera to Ixalidium, though he did not mention them in his text. Bolívar (1905: 226) characterized Barombia tuberculosa var. sublaevis in a single line of Latin text as “colour grass green, pronotal tubercles sub-obsolete”. Var. sublaevis was automatically synonymised with B.tuberculosa by Kirby (1910: 386). Ramme (1929: 311) repeated the synonymy without citing Kirby (1910) and listed material from Ouésso, Congo Republic. Otte (1995: 277) ignored the synonymy of var. sublaevis, making it a subspecies, but Mestre & Chiffaud (2009: 25) reinstated the synonymy (referencing the earlier synonymies of Kirby and Ramme). Bolívar (1908: 106) listed material of B.tuberculosa from Mukonje Farm, Cameroon, collected by R. Rhode (Zoological Museum, Hamburg University), that Massa (2020: 49-50) stated to be three females, one of which Massa considered to be typical “var. sublaevis”. Massa concluded that the degree of tuberculation was variable within a population, reconfirming the synonymy of var. sublaevis with B. tuberculosa. Rehn (1958: 3-5) described B.nassaui from a single specimen from Bitje (Bitye) on the basis of its more pronounced tubercular development of the thoracic dorsum relative to material of B.tuberculosa he had studied, which was in fact somewhat atypical. Barombia nassaui was synonymised by Dirsh (1966: 101). The increased production of the dorsal thoracic crest reported by Rehn may have resulted from allometric growth, since the hind femur length of his holotype male (16.3mm) is 12% larger than that of the material of B. tuberculosa (14.1-14.3mm) to which he compared it. reMarks Karsch’s type series of onemale and two females are all syntypes, since Karsch did not designate holotypes when more than one specimen was present (Holier 2010). This reality is not altered by the subsequent labelling of the male as holotype (DORSA BA 000504S01) and the two females as allotype and paratype (respectively DORSA BA 000504S02 and DORSA BA 000504S03). Accordingly, the single male syntype (DORSA BA 000504S01) is here designated as lectotype of Barombia tuberculosa Karsch. Images of the syntypes and their labels are shown in OSF (Cigliano etal. 2023). No revision of the genus Barombia has been undertaken. The genus is probably known from fewer than 30 specimens in museum collections globally. In line with the foregoing record of synonymies, critical examination of material, including male genitalia, from across the geographical range of Barombia has not so far yielded clear evidence that more than one species exists. Genus Ixalidium Gerstäcker, 1869 Ixalidium Gerstäcker, 1869: 220. TableIII, figs6 and 6a. t ype species .— Ixalidium haematoscelis Gerstäcker, 1869 by monotypy. redescription Small to medium size (Tables4-6). Males 16.5-20.2mm; females 23.6-29, with body length up to 50% greater than males and with more robust habitus (Fig.11A). Integument rugose and punctate, variably setose. Head Antennae: 17-segmented, about as long as or slightly longer than head and pronotum together, basal segments (apart from scape and pedicel) dorso-ventrally compressed, widening markedly at segment three, widest between 3 and 6, with 8-9 distinctly less compressed and 10-17 filiform. Head width across eyes distinctly less than pronotum length and less than pronotum width at its hind margin; head obliquely slanted in lateral view, with vertex produced and frons sometimes shallowly incurved between antennae; eyes ovoid, narrower above, oblique. Fastigium of vertex from above (Fig.4A) pro - jecting over lateral ocelli and antennal bases, shorter than its maximal basal width, with obtusely rounded apex and median carinula continuing on occiput; foveolar area obsolete; frontal ridge in anterior view narrowest immediately below vertex, widening between antennae, then narrowing above median ocellus; lateral carinae widening below ocellus and becoming obsolete towards clypeus. Thorax Pronotum low tectiform, median carina crossed by 2-3 sulci; prozona 3-4 times longer than metazona; dorsum from above widening steadily from fore margin to hind margin. Prosternal tubercle transverse, spathulate, almost straight-sided, sparsely to densely setose, anterior face flat to slightly concave, posterior face flat to slight convex; apical margin straight or slightly uneven, with rounded angles. Mesoand metathorax tectiform, with median carina; mesonotum without visible tegminal rudiments; metathorax raised posteriorly and with distinct lateral carinae above robust lateral projections which stiffen its lateral lobes above hind coxae; Mesosternal interspace broader than its length, widening posteriorly; mesosternal furcal suture with deep medial and lateral pits. Metaster- 511 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) nal interspace slightly broader than its length, narrowing posteriorly, tending to form two separate pits with medial portion of interspace continuous anteriorly with anterior portion of metasternum. Legs Fore and mid legs of typical acridoid appearance, unspecialized. Hind femur moderately robust, 3.1-3.9 times as long as maximum depth, male; 3.3-4.1 times, female (Tables4-6); hind knee with upper and lower lobes bluntly or acutely rounded; hind tibia with 8 outer and 9 inner spines; external apical spine absent; arolium large, rounded, in ventral view about as long as claw; claws thickened at base, apically strongly curved. Abdomen With median dorsal carina and with segments one and two distinctly raised, together with metathorax forming slight hump; tympanum large and sub-oval; tergites 9 and 10 fused laterally. External terminalia (Fig.5A-C) presenting nymph-like appearance, without specialised structures; supra-anal plate A E D F C G B Fig. 9. — Male terminalia and genitalia, Mazaea tristis (Sjöstedt, 1931) n. comb., Congo Republic. A, phallic complex, dorsal; C, same, lateral; B, same, ventral, epiphallus removed; D, aedeagus, posterior view; E, epiphallus, dorsal view; F, same, posterior view; G, terminalia, dorsal view. Scale bars: A, 1 mm; B-F, 0.5 mm; G, not to scale. 518 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Genus Rowellacris Ritchie& Hemp n.gen. urn:lsid:zoobank.org:act:216ED37B-FAC1-49B8-A046-BB3988AB4EE5 type species.— Ixalidium usambaricum Ramme, 1929. etyMology.— This new genus is named in honour of Charles Hugh Fraser Rowell in grateful recognition of his outstanding contributions to the biology and systematics of tropical locusts and grasshoppers over more than sixty years. description See family description. Small to medium size (see Measurements, Tables8; 10; 11). Males 18.5-24.75; Females 27.533.95. Integument rugose and punctate. Head Antennae ensiform, with c.16-17 segments, from 80% to 115% of combined length of head and pronotum. Fastigium of vertex 1.3 to 1.6 times as long as its basal width, with irregular transverse sulcus at base. Thorax Pronotum low tectiform, median carina intersected by 3 sulci, the first often indistinct. Prosternal tubercle transverse, chisel like, with anterior face oblique, apex widening, lateral edges rounded to slightly bilobate, sometimes slightly crescentic in cross-section with anterior margin shallowly concave. Mesonotum, short, occasionally (R.transiens (Ramme, 1929) n.comb.) with narrow strap-like tegminal scars, completely fused to integument, sometimes visible projecting from beneath hind margin of pronotum, on one or both sides just above lateral sutures separating dorsum from mesopleura. Metanotum slightly inflated. Legs Hind femora moderately stocky (length / max. depth, males: 3.1-3.75, females; 3.35-3.85); hind tibiae with seven outer and nine inner spines; external apical spine absent. Abdomen Tergites medially carinate with each segment in lateral view dorsally convex, tergites 1 and 2 slightly inflated; tympanum large, suboval, with ventral margin flattened or slightly concave. External terminalia (Fig.5D-G) with supra-anal plate divided into basal polygonal portion and movable triangular apical portion. Hind margin of basal portion distinctly sinuous with paired rounded flanges. In R.usambarica (Ramme, 1929) n. comb. last abdominal tergite (tergite 10) interrupted dorso-medially by basal portion of supra-anal plate; in R.transiens n. comb. tergite 10 continuous and thickened dorsally, with dorsally-projecting digitate median furcula; supra-anal plate strongly rugose; cerci simple, conical, densely covered in sensilla. Subgenital plate bulbous (by comparison to Ixalidium), of variable length (short in R.obscuripes n. comb.), with attenuate apex. Male genitalia Epiphallus (Figs13E, F; 14M-O; 15K-M) bridge-shaped, without ancorae; lateral plates concave in dorsal view; lateral sclerites elongated, irregular in outline, somewhat deflexed postero-dorsally; lophi bilobate, lobes pointed with inner pair directed medially and postero-dorsally, outer pair smaller and laterally directed; ventral margin of bridge forming a membranous cushion; bridge, lateral plates and adjoining membrane with numerous sensory pores. Cingulum.(Figs13B, D; 14E, G, H; 15B, C, G). Having sclerotised shell-like zygoma with anteriorly placed paired apodemes distinct (in R.usambarica n. comb. and R.transiens n. comb.), obsolescent (in R.obscuripes (Miller) n. comb., or absent (in undescribed species from East Usambara Mts); zygoma hind margin medially incurved in R.usambarica n. comb., and R.transiens n. comb., and forming sclerotised lateral horns in R.usambarica n. comb., or roundly excurved (R.obscuripes n. comb. and R.transiens n. comb.); rami of cingulum, covered by epiphallic membrane, forming inflated mitten-like lateral lobes with sclerotised ectophallic structures visible within, medially concave and externally convex; rami continuous with zygoma dorsally and fusing ventrolaterally with dorso-lateral margins of inflated bulbous ventral lobe. Arch of cingulum present, well-developed, joining zygoma to apical valves of endophallus; dorsolateral margins of cingular arch bilaterally inflated to form bulbous sub-dorsal lobe, strongly developed and visibly projecting caudad from beneath cingulum in dorsal view in R.usambaricum n. comb. and R.transiens n. comb., less developed and somewhat variable in different populations of R.obscuripes n. comb. Endophallus (Figs13D; 14E, J-L; 15F, H-J). In two sections with visible articulated break, paired endophallic apodemes separated apically, laterally flared dorsally, fused and medially ridged throughout most of their length; ejaculatory sac obsolete, reduced to a slight widening of the ejaculatory duct, before entering fused endophallic apodemes; apical endophallic sclerites fused, laterally compressed, slightly to moderately upcurved, forming tubular aedeagus enfolding phallotreme, within membranous sheath continuous with rami of cingulum; apex of aedeagus excurved, projecting dorsally beyond rami and ventral lobe; spermatophore sac reduced, situated dorsally at proximal end of apical sclerites, anterior to arch of cingulum. Female genitalia (Fig.12). Spermatheca with three diverticula (Fig.12A-C) arising from vestibule one above another: most ventral one short, sac-like, widening distally; middle one elongate sac-like, almost as long as dorsal ovipositor valves and apodemes together; dorsal one thin tubular, shorter than dorsal ovipositor valves, with apical and subapical diverticula, each ending in an apical ampulla (Fig.12A-C); vestibule with elongate open slit ventrally between ventral valves of ovipositor (Fig.12B). 519 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) Coloration (Figs2C-E; 19E, F). Rowellacris Ritchie& Hemp n.gen. males have similar range of overall patterning to Ixalidium, with paler morphs dorsally buff-coloured, contrasting with darker brown lateral parts of thorax and darker morphs having all paler markings indistinct. Typical patterning includes dorsal longitudinal lateral pale bands beginning behind eyes, converging towards median carina in prozona of pronotum, then either continuous or interrupted by darker pigment, before diverging and continuing obliquely downwards across thoracic pleura to hind coxae; metaepimeron black. Hind femora externally mottled brown or olive grey, darker on upper and lower marginal areas; internal upper marginal area mottled olive grey proximally, becoming darker towards knee, sometimes with pale buff oval marking in proximal half; internal medial area mainly black with pale mark towards knee, sometimes with paler area medially; lower ABDE C F G Fig. 12. — Female genitalia: A-C, Rowellacris n. gen. sp. (Tanzania, E Usambara Mts, Sigi); D-G, Tangana asymmetrica Ramme, 1929 (Tanzania, Pangani Coast): A, Spermatheca and ovipositor valves, dorsal view; B, same, ventral view; C, same, lateral view; D, Spermatheca and ventral ovipositor valves (dorsal valves removed), dorsal view; E, same, ventral view, with bristle inserted through vestibule into lumen of spermathecal bursa; F, same, lateral view; G, spermathecal vestibule, duct and diverticula, ventral view, enlarged. Scale bars: 1 mm. 520 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. internal carinula and carina and lower marginal area red in proximal three fifths, fading or darkening towards knee. Hind tibia varying from pale greyish buff to grey brown, pale mauve, violet or blackish, but never red; tibial spines black-tipped. Abdomen with lateral shiny black bands reaching from tergite 2 to tergites 5 or 6, fading caudad. Ventral surface of thorax and abdomen pale buff to light brown. included species Rowellacris usambarica (Ramme, 1929) nom. rev., n. comb. Rowellacris transiens (Ramme, 1929) n. comb. Rowellacris obscuripes (Miller, 1929) nom. rev., n. comb. Rowellacris usambarica (Ramme, 1929) nom. rev., n. comb. (Figs1; 2C, D; 4B; 5G; 13; 21D; Tables8; 9) Ixalidium usambaricum Ramme, 1929: 307. Ixalidium haematoscelis – Dirsh 1966: 103 (incorrectly synonymised; here recalled from synonymy). type Material exaMined.— Holotype. Tanzania • ♂; [Lushoto District], [West] Usambara Mountains, Muafa; [c 1200-1300m a.s.l.]; J. Buchwald leg.; DORSA BA000802S01; Collection Object 1501239; 1d78f5f7-d185-4827-87e9-ed12890fc309; MfN, Berlin. Paratype. Tanzania • ♂; same collection data as for preceding; DORSA BA000802S03; MfN, Berlin; MfN URI: http://coll.mfnberlin.de/u/d87ebc. other Material exaMined.— Tanzania • 2 ♂ ; West Usambara Mts, Wilhelmstal [= Lushoto]; F.E. Zeuner leg.; NHMUK • 1 ♂ ; West Usambara Mts, West foot of mountains, Mombo, Riverine forest; 9.VI.1967; N.D. Jago; DNA voucher B5, extracted 19.X.2022, Box: SA00924142, Tube: FD18757457; NHMUK 015134149 • 1 ♂ ; West Usambara Mts, Ndelemai Forest; III.2022; C. Hemp leg.; Coll. CH • 1 ♂ ; West Usambara Mts, Muafa [Lushoto District]; III.2022; C. Hemp leg.; Coll. CH. diagnosis.— Basal portion of supra-anal plate with flanges on posterior margin not continuous with outer edges (Figs5, G; 13A ). Cingulum with well-developed apodemes (Fig.13B-D). Posterior margin of cingulum medially excavated with pointed and sclerotised lateral processes (Fig.13B). Sub-dorsal lobe prominently inflated and exposed dorsally, slightly bilobate (Fig.13B). Measurements: Table8. distribution Known only from submontane forest sites at Muafa, Ndelemai Forest, Lushoto and riverine forest at Mombo, West Usambara Mountains. Dissection of the genitalia of the male paratype from Muafa and comparison with recently collected specimens of this species from Muafa and the nearby Ndelemai Forest indicate that R.usambarica n. comb. (Fig.13A-H) has a restricted distribution within the West Usambara Mountains. It is replaced by several other closely-related Rowellacris Ritchie& Hemp n.gen. species, both on neighbouring Eastern Arc mountains and within the West Usambara Mts. The single male paratype collected, along with three females, by Vosseler from Amani (East Usambara Mts) has not been dissected, but numerous other specimens from Amani and its environs, both in the NHMUK collection and collected recently have been dissected. These all show character states in the morphology of the cingulum that are consistently distinct from West Usambara material and all evidently belong to a single species. Accordingly, this Amani material has been assigned to a third, as yet undescribed species of Rowellacris Ritchie& Hemp n.gen. (unpublished data). The single male paratype of I.usambaricum collected by Karasek from Tanga has been Table 8. — Measurements in mm, Rowellacris usambarica (Ramme, 1929) n. comb., Tanzania, West Usambara Mts. Antenna length Head width Pronotum length Hind femur length Hind femur depth Femur length / depth Total body length Males n4 4 4 4 4 4 4 Range 6.11-6.93 3.31-3.51 4.2-4.63 10.22-11.66 3.26-3.59 3.13-3.25 18.52-22.85 Mean 6.57 3.42 4.38 10.91 3.43 3.18 20.2 Table 9. — Assignment to species of Ramme’s type series of Rowellacris usambarica (Ramme, 1929) n. comb. (MfN, Berlin). Localities (collector) Species Type specimens West Usambara, Muafa (J. Buchwald) Rowellacris usambarica n. comb. [based on dissection of topotypic paratype] Holotype male, 1 paratype male (MfN) East Usambara, Amani (Vosseler) Rowellacris sp. 1 [only species known from Amani] Paratypes, 1 male, 2 females (MfN); 1 female (NHMUK) Tanga (Karasek) Rowellacris cf. obscuripes n. comb. [based on dissection of male paratype] Paratype, 1 male (MfN) Buloa, nr Tanga (P. Lucker) Uncertain, not seen, but most likely R. cf. obscuripes n. comb., if not Tangana asymmetrica Paratype, 1 female (MfN) 521 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) dissected and found to belong to the related coastal forest species Rowellacris obscuripes (Miller, 1929) n. comb. The records of R.usambarica n. comb. from East Usambaras and Mlinga Mountain (Magroto) by Hochkirch (1996: 204) are misidentifications of two different undescribed species of Rowellacris Ritchie& Hemp n.gen. (material studied). The record of I.usambaricum from Lutindi Forest (Hemp etal. 2016: 216) represents yet another undescribed species of Rowellacris Ritchie& Hemp n.gen. Yet another undescribed species of this genus occurs in the Irente area west of Lushoto. reMarks Ramme (1929: 307-308) described I.usambaricum from a mixed species series here recognised as comprising three distinct species (Table9). The holotype male and two paratypes, one male and one female, were collected by J. Buchwald at Muafa (West Usambara Mountains). A DG H FE BEjd Ejd Ca Zyg Zyg Ca Ca Cr Cut Cut Cut Sdl Cut Cr Bv Av LpLp Lp Lp Lsc Lsc Lsc Lo Lo Lo Av Av Ae B B As Ae Vla Vl Vl Vl Ejd C Fig. 13. — Rowellacris usambarica (Ramme, 1929) n. comb., male genitalia: A, end of abdomen, dorsal view; B-D, phallic complex (epiphallus removed); B, dorsal view (rami slightly separated); C, ventral view (pallium removed); D, lateral view, left side; E-H, epiphallus: E, dorsal view; F, postero-dorsal view; G, lateral view, left side; H, same, right side. Provenance: A-H, West Usambara Mountains, Tanzania; A, paratype, Muafa, B-H, Ndelemai Forest. Scale bars: 0.5 mm, except under Figure A, where 1 mm. Abbreviations: see Material and Methods. 522 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Rowellacris transiens (Ramme, 1929) n. comb. (Figs5D, E; 14; Table10) Ixalidium transiens Ramme, 1929: 308-309. Ixalidiumhaematoscelis – Dirsh 1966: 103 (incorrectly synonymised. Recalled from synonymy by Johnsen& Forchhammer [1975: 38-41]). type Material exaMined.— Holotype. Tanzania • ♂; [Lushoto District], [East] Usambara, Nguelo [Ngwelo]; [4°44’S, 38°29’E]; [Ernst?] Heinsen leg.; MfN. ‘Allotype’ [Paratype]. Tanzania • ♀ [Lushoto District], [East] Usambara, Nguelo [Ngwelo]; [4°44’S, 38°29’E]; [Ernst?] Heinsen leg.; MfN. other Material exaMined.— Tanzania • All material: Lushoto District, East Usambara Mountains • 6 ♂ , 3 ♀ , 3 nymphs; Soni; 4°51’S, 38°22’E; 17.IX.1950; J. Phipps leg.; NHMUK • 2 ♂ , 1 ♀ ; Kihuhwi Bridge, 7miles East of Amani; 5°13’S, 38°41’E; A Fu Fu Cr Ca Ca Zyg Cr Cr Ca Zyg Ejd Vla VI Av Av Ae Ae Sps Sps Ejd Ae Av Lo Lp Lsc Lsc LpB Lo AeAc Ac Cut Cut As Av As Vl E JK GH I M N O P L C B DF Fig. 14. — Rowellacris transiens (Ramme, 1929) n. comb., male genitalia: A-D, end of abdomen: A, dorsal view; B, lateral view, left side; C, holotype, dorsal view (with tip of supra-anal plate covered by subgenital plate); D, same, lateral view, left side; E-L, internal genitalia; E-I, genitalia with epiphallus removed; E, lateral view, left side; F, posterior view; G, H, dorsal view; I, ventral view; J-L, Endophallus with cingulum and ventral lobe removed: J, dorsal view; K, ventral view (only basal portion of apical valves visible); L, lateral view, left side; M-P, epiphallus; M, dorsal view; N, dorso-posterior view; O, ventral view; P, later view, left side. Provenance: A-O, East Usambara Mountains. Scale bars: 1 mm, except under figure P, where 0.5 mm. Abbreviations: see Material and Methods. 523 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) 27.VIII.1937; E. Burtt leg.; NHMUK • 1 ♂ ; Kihuhwi Bridge, 7miles East of Amani; 5°13’S, 38°41’E; 28.VIII.1938; E. Burtt leg., NHMUK. • 1 ♂ ; Kwamtili Plantation; 4°55’S, 38°44’E; III.1952; J. Phipps leg.; NHMUK • 5 ♂ , 4 ♀ , 2 nymphs; Sigi, nr Amani; 5°6’S, 38°39’E; 18-31.XII.1965; N.D. Jago leg.; NHMUK • 2 ♂ , 1 ♀ ; Sigi, nr Amani; 5°6’S, 38°39’E; 2-11.IV.1966; N.D. Jago leg.; NHMUK • 1 ♂ ; Bomole Summit, near Amani; 5°6’S, 38°37’E; 3.IV.1966; N.D. Jago leg.; NHMUK • 1 ♂ , 1 ♀ ; Longuza Forest Reserve; 5°4’S, 38°41’E; 15.IV.1966; N.D. Jago leg.; NHMUK • 1 ♂ ; Derema Forest; 5°38’S, 37°30’E; 24.XII.1965; N.D. Jago leg.; NHMUK • 1 ♂ ; Amani, Amani Nature Reserve, nr HQ; 5°5’S, 38°40’E; VII.2016; C. Hemp leg.; submontane forest; Coll. CH • 1 ♂ ; Amani, Waldrand (forest edge); 5°5’S, 38°40’E; X.2002; C.Hemp leg.; Coll. CH • 1 ♂ ; Sigi, trail at night; 5°6’S, 38°39’E; III.2012; C. Hemp leg.; Coll. CH. d iagnosis .— Male terminalia of unique form, with projecting medial furcula (Fig.5D, E). Cingulum with well-developed apodemes with expanded tips (Fig.14G-I). Posterior margin of cingulum medially excavated but lacking lateral processes (Fig.14G, H). Sub-dorsal lobe prominently inflated and exposed dorsally, but unilobate (Fig.14G, H). Measurements: Table10. distribution R.transiens n. comb. is known only from relict forest patches around Amani, East Usambara Mountains, where Hochkirch (1996) reported the species from 11 different survey sites and considered R.transiens n. comb. to be an indicator species for intact forest canopy (Hochkirch 1996: 209). Hochkirch (2014) gave the name drumming grasshoppers to members of the genus Ixalidium, based on drumming observed in R.transiens n.comb. However drumming behaviour has not been observed in Ixalidium sjostedti and Ixalidium sp. from the North Pare Mts. in recent experiments by one of us (CH), whereas it is has been observed in both Rowellacris Ritchie& Hemp n.gen. and Tangana (see Bioacoustics). The conservation status of R.transiens n.comb. was assessed as vulnerable by Hochkirch (2014, 2020) and Gereau etal. (2016) due to forest destruction. history Ramme (1929: 311) reported that his Ixalidium (now Rowellacris Ritchie& Hemp n.gen.) transiens represented a transitional stage between Ixalidium usambaricum and Tangana asymmetrica, because of the presence of a furcula on tergite 10 (Fig.5D, E), which he considered a precursor to the asymmetric prong in Tangana (Fig.5H). However the furcula is an autapomorphy of R.transiens and the genital morphology of this species and all other Rowellacris Ritchie& Hemp n.gen. species is otherwise very consistent and quite distinct from that of Tangana. Johnsen& Forchhammer (1975: 3841) correctly recalled this species from Dirsh’s (1966: 103) synonymy under I.haematoscelis and figured the distinctive male external and internal genitalia. Ramme’s unique holotype male of I.transiens has the apical section of the supra-anal plate deflexed into the abdomen (Ramme 1929: fig.31) and completely covered by the subgenital plate (see Fig.14C, D), which led Johnsen& Forchhammer (1975) to believe that the tip was missing. Rowellacris obscuripes (Miller, 1929) nom. rev., n. comb. (Figs 1; 2E; 5F; 15;Tables9; 11) Ixalidium obscuripes Miller, 1929: 80. Table 10. — Measurements in mm, Rowellacris transiens (Ramme, 1929) n. comb., Tanzania, East Usambara Mts (NHMUK). Antenna length Head width Pronotum length Hind femur Length Hind femur depth Femur length/ depth Total body length Males n9 10 10 10 10 10 10 Range 7.15-7.7 3.35-3.55 4.25-4.85 11.55-12.65 3.3-3.55 3.4-3.72 19.6-23.2 Mean 7.47 3.47 4.52 12.05 3.42 3.52 21.58 Females n6 6 6 6 6 6 6 Range 7.3-8.7 4.05-4.45 5.95-7.1 15.65-17.6 4.2-4.6 3.65-3.83 28.4-32.75 Mean 7.93 4.26 6.43 16.38 4.38 3.74 30.74 Table 11. — Measurements in mm, Rowellacris cf. obscuripes (Miller. 1929) n. comb., Kenya, Mrima Hill (NHMUK). Antenna length Head width Pronotum length Hind femur length Hind femur depth Femur length/ depth Total body length Males n10 9 10 10 10 10 10 Range 5.75-6.7 3.4-4.35 4.05-4.35 11.2-12.0 3.35-3.65 3.21-3.36 19-20.65 Mean 6.08 4.06 4.25 11.56 3.53 3.28 19.91 Females n10 10 10 10 10 10 10 Range 6.1-7.5 4.15-4.4 5.8-6.3 14.5-15.75 4.2-4.55 3.37-3.62 27.55-31.85 Mean 6.69 4.26 6.07 15.28 4.42 3.46 29.19 524 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Ixalidiumhaematoscelis – Dirsh 1966: 103 (incorrectly synonymised; here recalled from synonymy). type Material exaMined.— Holotype. Tanzania • ♂; Tanga District, Msimbazi River; 5.XII.1926; N.C.E. Miller leg.; NHMUK. o ther Material exaMined .— Tanzania • 1 ♂ ; Tanga; A. Karasek leg.; paratype of Ixalidium usambaricum; MfN URI: http://coll. mfn-berlin.de/u/44d6c4; DORSA BA000802S05; MfN • 1 ♂ ; [Tanga Region, Muheza District], [Mlinga Mountain], Magrotto [=Magoroto Forest Estate]]; 05°07’0”S, 38°45’0”E; [700-1069m a.s.l.]; 27.VII.1994; A. Hochkirch leg.; on forest path; DNA voucher E2, extracted 19.X.2022, Box SA00924142, Tube: FD18757436; NHMUK 015134130; Coll. AH • 1 ♂ ; Tanga Region, nr Tanga, Amboni Caves; 05°03’60”S, 39°2’60”E; 27.I.1998.; ground litter under tree; Coll. AH • 2 ♂ , 1 ♀ ; Manza Bay, Kwale Island; 4°57’30”S, 39°10’17”E ; 1-2m a.s.l.; IV. 2021; C. Hemp leg.; coastal forest leaf litter; Coll. CH • 1 ♀ ; Manza Bay, Kwale Island, Sacred Forest; 4°57’43”S, 39°8’28”E; 12m a.s.l.; X.2021; C. Hemp leg.; Coll. CH. Kenya • 10 ♂ , 21 ♀ ; Shimba Hills; III.1941; V.G.L. Van Someren leg.; NHMUK • 4 ♀ ; Shimba Hills; VII.1939; V.G.L. Van A D F GE HI J K L M N B Zyg Zyg Zyg Ae Cr Cr Ca Sps Sdl Sps Sps Cr Av VI VI VI VI VI Av Av Ac Av Ae Ejd Cut Cut Cut Cut Cut Cut Ejd Ae Ae As As Ac B B Lsc Lsc Lsc Lsc Lo Lp Lo Lo Ae Ae Ae C Fig. 15. — Rowellacris obscuripes (Miller, 1929) n. comb., male genitalia: A, end of abdomen, dorsal view; B-N, Internal genitalia; B-J, genitalia with epiphallus removed: B, dorsal view; C, lateral view, left side; D, ventral view; E, F, Endophallus with ventral lobe attached and with cingulum removed, showing sub-dorsal lobe underlying cingulum; E, dorsal view, F, lateral view; G, cingulum after removal, lateral view, left side; H-J, Endophallus with ventral lobe removed: H, lateral view, left side; I, dorsal view, J, ventral view (only basal portion of apical valves visible); K-N, Epiphallus: K, dorsal view; L, dorso-posterior view; M, posteroventral view; N, lateral view, left side. Scale bars: A-M, 1 mm; N, 0.5 mm. Provenance: a-N, Diani, Kenya. For key to abbreviations, see Material and Methods. 525 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) Someren leg.; NHMUK • 1 ♂ , 1 ♀ , 1 nymph; Shimba Hills, W side, scarp road, 4°15’26”S, 39°23’16”E; 19.IX.1982; N.D. Jago leg.; forest; NHMUK • 1 ♂ ; Tiwi; III.1941; V.G.L. Van Someren leg.; NHMUK • 1 ♂ , 1 ♀ ; Diani Beach, 22miles S of Mombasa; 27.III.1953; E.S. Brown leg.; NHMUK • 1 ♂ ; Diani Beach, 22miles S of Mombasa; 30.III.1953; E.S. Brown leg.; Julbernardia /Manilkara forest; NHMUK • 3 ♂ , 7 ♀ , 2 nymphs; Mangea Hill, nr summit; 03°16’S, 39°43’E; 1500 feet a.s.l.; 1.III.1988; N.D. Jago, J.P. Grunshaw, I.A.D. Robertson leg.; NHMUK • 4 ♂ , 2 ♀ ; Kwale District, Mrima Hill, S of Kikoneni, forest; 4°29’9”S, 39°16’10”E; 800 feet a.s.l.; 21.IX.1982; N.D. Jago leg.; NHMUK • 11 ♂ , 12 ♀ , 4 nymphs; Kwale District, Mrima Hill, SW side, upper slope, forest; 4°29’9”S, 39°16’10”E; 500-800 feet a.s.l.; 29.1.1990; J.M. Ritchie, M.N. Mungai, J. Muli leg.; NHMUK • 2 ♂ , 2 ♀ ; North Diani Beach, 20miles S of Mombasa, 1km N of Tradewinds Hotel; 16.IV.1975; 100metres wide foreshore and exploited coastal thicket, 100-500metres from beach; 4°18’S, 39°35’E; c.20 ft a.s.l.; I.A.D.& A. Robertson leg.; NHMUK • 5 ♂ , 6 ♀ ; W of Gazi, Mombasa to Ramisi road, Gogoni Forest; 21.IX.1982; N.D. Jago leg. ; NHMUK • 1 ♂ , 3 ♀ , 3 nymphs; Kwale District, Kilibasi Hill, SW side, upper and lower slopes; 3°57’S, 38°57’E; 1400-2700 ft a.s.l.; 27.I.1990; J.M. Ritchie& M.N. Mungai leg.; forest and mist forest; NHMUK • 8 ♂ , 13 ♀ , 1 nymph; Dzombo [Jombo] Hill, upper slope, N side; 4°26’S, 39°13’E; 1000-1300 feet a.s.l.; 30.I.1990; J.M. Ritchie& M.N. Mungai leg.; forest; NHMUK • 1 ♂ ; Kwale District, 20kms N of Lunga Lunga; 4°33’S, 39°08’E; 31.I. 1990, J.M. Ritchie& M.N. Mungai leg.; lowland dry forest; NHMUK • 1 ♀ ; Cha Simba Limestone outcrop; 03°44’S, 39°42’E; 650 feet a.s.l.; 29.II.1988; N.D. Jago, J.P. Grunshaw, I.A.D. Robertson leg.; Gymnocarpus / Pandanus (Ficus) / Euphorbia forest; NHMUK • 4 ♀ ; plain between Linango and Kwale, Route C106, Godoni Forest; 4°09’S, 39°26’E; 18.IX.1982; N.D. Jago leg.; NHMUK • 2 ♀ ; 3.5kms NW of Jaribuni; 3°38’S, 39°44’E; N.D. Jago leg.; savanna woodland with cycads and aloes; NHMUK. diagnosis.— Subgenital plate shorter than other species of Rowellacris Ritchie& Hemp n.gen. (Fig.5F). Posterior margin of basal section of supra-anal plate strongly concave, with flanges at outer edges (Figs5F; 15A). Cingulum hind margin strongly convex, largely or completely covering sub-dorsal lobe (Fig.15B). Sub-dorsal lobe strongly bilobate posteriorly (Fig.15E). Measurements: Table11. distribution Originally described by Miller (1929) from the riverine forest bordering the lower Msimbazi River which flows through the centre of Dar Es Salaam, the type locality of R.obscuripes n.comb. has not yielded any further specimens since then. The type locality is now severely affected by urban encroachment entailing habitat destruction, waste dumping and pollution as well as bi-annual flooding worsened by upstream deforestation in the Pugu Hills and land-use change (World Bank 2022). Morphologically similar specimens are known from patches of woodland, dry forest and thicket at Magoroto, Amboni, Tanga (paratype of R.usambaricum n.comb.), from coastal scrub forest on coral on Kwale Island (Manza Bay) and Fish Eagle Point and coastal forest on Kilulu Hill in Tanzania, as well as from Mrima Hill, Jombo Hill, Kilibasi Hill (co-occurring with I.haematoscelis), Shimba Hills, Diani, Cha Simba, Godoni Forest, Gogoni Forest, Tiwi, among other sites in Kenya. The measurements given (Table11) are derived from the long series from Mrima Hill, while drawings of morphology are from the Diani population. reMarks The terminalia of R.obscuripes n.comb. are distinctive (see diagnosis). Minor variations in male genital morphology occur between the different populations assigned to this species, but they all share the widely-spaced and protuberant flanges on the male supra-anal plate (Fig.5F). The male specimen from Jadini, Kenya, figured by Johnsen& Forchhammer (1975: 41, fig.18) as I.haematoscelis, has been assigned to R.obscuripes n.comb. by this character. The genitalia of the unique holotype of R.obscuripes n.comb. are not available for dissection. However, recently collected specimens from Kwale Island in Manza Bay are close to the holotype in terms both of their external morphology and their Mt DNA profile (Price et al, in preparation). Specimens from sub-coastal localities in Kenya (Shimba Hills, Mangea Hill) are also genetically and morphologically more closely similar to this taxon than to any other. Continuing research to characterize the various populations currently assigned to R.obscuripes n.comb. based on DNA and genital morphology, may lead to the recognition of new species. In synonymizing three species now assigned to Rowellacris Ritchie& Hemp n.gen. under Ixalidium haematoscelis Dirsh (1966: 103-104, fig.42) substituted a drawing of the highly characteristic genitalia of an undescribed Rowellacris Ritchie& Hemp n.gen. species from Amani, East Usambara Mts, for the very different genitalia of Ixalidium haematoscelis, which he had apparently never dissected, since no genitalia preparations of his exist in the collections of the NHMUK. This error misled later workers, including Johnsen& Forchhammer (1975). Genus Tangana Ramme, 1929 Tangana Ramme, 1929: 309. Ixalidium – Uvarov 1941: 30 (incorrect synonymy).— Johnston 1956: 294. Tangana – Dirsh 1965: 320 (ignoring Uvarov’s synonymy).— Johnsen& Forchhammer 1975: 38 (recalled from synonymy). — Hemp 2017: 188. t ype species . — Tangana asymmetrica Ramme, 1929, by monotypy. Tangana asymmetrica Ramme, 1929 (Figs1; 4C; 5H; 12D-G; 16; 17; 20B; 21H-J; 22F; Table12) Tangana asymmetrica Ramme, 1929: 310. Ixalidium asymmetricum – Ramme 1929; incorrectly synonymised by Uvarov (1941: 30); recalled from synonymy by Johnsen& Forchhammer (1975: 38). type Material exaMined.— Holotype. Tanzania • ♂; Tanga; A.Karasek; MfN. Paratype. Tanzania • ♀; Tanga; [5°4’S, 39°6’E]; A. Karasek leg.; NHMUK • 2 ♂ ; Tanga; [5°4’S, 39°6’E]; A. Karasek leg.; MfN, Berlin. 526 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. other Material exaMined.— Tanzania • 4 ♂ ; Korogwe, Handeni, Kwa Mbisi; 5°25’27”S, 38°1’10”E; 18.IX.1952; E. Burtt leg.; NHMUK • 6 ♂ , 3 ♀ ; Korogwe, Handeni, Kwa Mbisi; 5°25’27”S, 38°1’10”E; 20.IX.1952; E. Burtt leg.; NHMUK • 1 ♀ ; Tanzania, Korogwe, Handeni, Kwa Mbisi; 5°25’27”S, 38°1’10”E; 19.IX.1952; E. Burtt leg.; NHMUK • 1 ♂ ; Morogoro District, Kingolwera [Kingolwira]; 6°47’S, 37°46’E; 7.XII.1953; E. Burtt leg.; NHMUK • 1 ♂ ; Morogoro District, same collection data as for preceding; 10.IX.1952; E.Burtt leg.; NHMUK • 1 ♀ ; same collection data as for preceding; 18.XII.1953; E. Burtt leg.; NHMUK • 2 ♀ , 1 nymph; Muheza District, Mlingano, Ngomeni; 5°09’00”S, 38°53’60.0”E; IV.1952; J.Phipps leg.; NHMUK • 1 ♂ ; same collection data as for preceding; III.1952; J. Phipps leg.; rubber bush; NHMUK • 2 ♀ ; same collection data as for preceding; 9.IV.1952; J. Phipps leg.; NHMUK • 1 ♀ ; same collection data as for preceding; 30.III.1952; J. Phipps leg.; NHMUK • 1 ♀ ; same collection data as for preceding; V.1953; J. Phipps leg.; NHMUK • 1 ♂ , 1 ♀ ; Dar es Salaam; 6°48’S, 39°17’E; 24.I.1964; E. Burtt leg.; NHMUK • 1 ♂ , 1 ♀ ; same collection data as for preceding; 26.I.1964; E. Burtt leg.; NHMUK • 3 ♂ , 7 ♀ ; same collection data as for preceding; 27.I.1964; E. Burtt leg.; NHMUK • 1 ♂ , 2 ♀ ; same collection data as for preceding; 28.I.1964; E.Burtt leg.; NHMUK • 1 ♂ , 3 ♀ ; same collection A D BC E Fig. 16. — A-E, Tangana asymmetrica Ramme, 1929, male paratypes, Tanzania, Tanga (A. Karasek), MFN, Berlin. A-D, internal genitalia, dextral paratype (MfN URI http://coll.mfn-berlin.de/u/a08979): A, Epiphallus, postero-dorsal view; B-D, genital complex (epiphallus removed); B, dorsal view; C, ventral view; D, lateral view, left side. E, terminalia, sinistral paratype, dorsal view (MfN URI http://coll.mfn-berlin.de/u/9aa74a). Image E by courtesy of MfN, Berlin. Scale bars: A, 0.2 mm; B-D, 0.5 mm; E, not to scale. 527 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) data as for preceding; 29.I.1964; E. Burtt leg.; NHMUK • 1 ♂ , 1 ♀ ; same collection data as for preceding; 30.I.1964; E. Burtt leg.; NHMUK • 2 ♂ , 5 ♀ ; same collection data as for preceding; 31.I.1964; E.Burtt leg.; NHMUK • 4 ♀ ; same collection data as for preceding; 1.II.1964; E. Burtt leg.; NHMUK • 1 ♀ ; same collection data as for preceding; 27.II.1964; E. Burtt leg., NHMUK • 1 ♂ ; Dar es Salaam, University Campus; 17.II.1998; A. Hochkirch leg.; under trees; Coll. AH • 1 ♂ ; Pangani District, Kigombe [Sisal] Estate; 5°19’S, 39°1’59”E; III.1952; J. Phipps leg.; NHMUK • 14 ♂ , 9 ♀ , 3 nymphs; Nguru Mountains, above Turiani; 6°09’S, 37°36’E; 5-7.XI.1964; N.D. Jago leg.; montane forest; NHMUK • 12 ♂ , 7 ♀ , 3 nymphs; Nguru Mountains, east foot, Mtibwa Forest Reserve, near Turiani; 6°07’S, 37°39’E; 5.XI.1964; N.D. Jago leg.; dry woodland; NHMUK • 1 ♂ , 1 ♀ ; Kisarawe, Kazimzumbwi Forest Reserve; I.2016; C. Hemp leg.; lowland wet forest; Coll. CH • 1 ♂ ; same collection data as for preceding; V.2016; C. Hemp leg.; Coll. CH • 1 ♀ ; same collection data as for preceding; VIII.2017; C. Hemp leg.; Coll. CH • 1 ♀ ; Pangani Coast, Turtle Beach; <100m a.s.l.; 5°24’S, 38°59’E; I.2000; C. Hemp leg.; Küstenwaldboden [coastal forest floor]; Coll. CH • 2 ♂ ; Pangani Coast, Turtle Beach; <100m a.s.l.; XII.2000; C. Hemp leg.; Waldrest [forest remnant]; Coll. CH • 1 ♀ ; Pangani Coast, zw. Kabuko-Mwera; 300m a.s.l.; II.2000; C. Hemp leg.; Küstenwald [coastal forest]; Coll. CH • 1 ♂ ; Pangani Coast, Caspary Grundstück [Caspary property]; IX.2011; C. Hemp leg.; Waldboden [forest floor]; Coll. CH • 3 ♂ , 1 nymph; Udzungwa Mts, Sanje trail; 7°45’54.3”S, 36°53’23.9”E; [886m a.s.l.]; 5.XII.1997; A. Hochkirch leg; grasses; Coll. AH • 1 ♂ ; Nguru Mts, Site T1; 30.I.1998; A. Hochkirch leg.; litter under mango tree; Coll. AH • 1 ♂ ; same collection data as for preceding; 3.II.1998; A. Hochkirch; Coll. AH. Kenya • 7 ♂ , 6 ♀ ; Tana River District, Tana River Primate National Reserve, Mchelelo Forest; 1°53’S, 40°08’E; 4-6.II.1990; J.M. Ritchie, M.N. Mungai, J. Muli leg.; NHMUK • 1 ♂ ; Kwale District, Dzombo [Jombo] Hill, upper slope, north side; 4°26’S, 39°13’E; 1000-1300 ft a.s.l.; 30.I.1990; J.M. Ritchie, M.N. Mungai, J. Muli leg.; forest; NHMUK • 2 ♂ , 5 ♀ ; Lamu District, Witu Forest Reserve, 5km E of Witu; 2°23’S, 40°29’E; 150 ft a.s.l.; 10.VI.1975; I.A.D.& A.Robertson leg.; NHMUK. redescription Small to medium size (Table12), but typically larger than Ixalidium. Males 22-26mm; females 27.5-31.5. Integument rugose and punctate. Head Antennae differentiated (Dirsh 1965), 17-segmented, about as long as head and pronotum together, basal segments (apart from scape and pedicel) dorso-ventrally compressed, ensiform, widening markedly at segment three, widest between 3 and 6, with 8-9 distinctly less compressed and 10-17 filiform. Head width across eyes distinctly less than pronotum length and less than pronotum width at its hind margin; head obliquely slanted in lateral view, with vertex produced and frons forming shallow obtuse angle between antennae; eyes ovoid, narrower above, oblique. Fastigium of vertex from above (Fig.4C) projecting over lateral ocelli and antennal bases, its maximal basal width about 1.5 times its length, with narrowly rounded rectangular apex, more angular than Ixalidium and Rowellacris Ritchie& Hemp n.gen.; median carinula cut by indistinct irregular transverse sulcus at base of fastigium, continuing onto occiput; foveolar area obsolete; frontal ridge in anterior view narrowest immediately below vertex, becoming sulcate with lateral carinae, widening between antennae, then narrowing above median ocellus; carinae subparallel below ocellus, becoming divergent and obsolete towards clypeus. Thorax Pronotum low tectiform, median carina crossed by 2 sulci; prozona 3-4 times longer than metazona; dorsum from above widening steadily from fore margin to hind margin. Prosternal tubercle transverse, tapered, wedge-shaped, widening laterally towards apex, sparsely setose, anterior face oblique, flat to slightly concave, posterior face vertical, flat to slight convex; apical margin slightly trilobate, with rounded angles. Mesoand metanotum tectiform, slightly raised, with median carina; mesonotum short, partly covered by metazona of pronotum, with lateral tegminal rudiments often concealed by metazona; metanotum with distinct longitudinal lateral carinae forming sharp angle at upper margin of epimeron 3; episternum 3 forming robust lateral projections above hind coxae. Mesosternal interspace broader than its length, widening posteriorly; mesosternal furcal suture with medial and lateral pits narrow. Metasternal interspace slightly broader than its length, narrowing posteriorly, tending to form two separate pits with medial portion of interspace continuous anteriorly with anterior portion of metasternum. Legs Fore and mid legs of typical acridoid appearance, unspecialized. Hind femur moderately robust, 3.2-3.7 times as long as maximum depth, male; 3.4-3.8 times, female (Table12); hind knee with upper and lower lobes bluntly Table 12. — Measurements in mm, Tangana cf. asymmetrica (Ramme, 1929) (Tanzania, Nguru Mts) (NHMUK). Antenna length Head width Pronotum length Hind femur Length Hind femur depth Femur length/ depth Total body length Males n9 10 10 10 10 10 10 Range 6.9-8.6 3.8-4.1 4.8-5.15 12.45-14.35 3.75-4.1 3.2-3.63 22.35-25.85 Mean 7.92 3.95 4.94 13.58 3.89 3.49 23.84 Females n8 10 10 10 10 10 10 Range 6.6-8.1 4.2-4.5 5.95-6.5 15.05-16.55 4.2-4.5 3.48-3.73 27.95-31.25 Mean 7.45 4.29 6.16 16.02 4.41 3.63 29.33 534 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Table 13. — Major morphological characters of female and male genitalia of the family Ixalidiidae Hemp, Song & Ritchie n. fam. and related families of Acridoidea. Symbols: –, inapplicable character; ?, missing data; 0/1, polymorphic character. ‘Traffic light’ colour coding indicates character states believed to be consistently shared with Ixalidiidae Hemp, Song & Ritchie n. fam. (green); partially shared (orange); or not shared (red). Characters (described state = 1 unless otherwise stated) Ixalidiidae n. fam. Pamphagodidae Pamphagidae Pyrgacrididae Lentulidae Tristiridae Ommexechidae Romaleidae Acrididae Notes and references Female Genitalia Two basal branches to spermathecal duct 0*/1 0† 0 0 0** 0§ 0** 0** 0** *0 in Ixalidium; **data incomplete; §Cigliano (1989a); †Descamps (1966). More than 2 distal spermathecal diverticula 0*/1 0§ 0 0 0 0 0/1** 0 0 *0 in Ixalidium; **Slifer (1940: 217); Amédégnato (1977); Ronderos (1979); §Descamps (1966). Male genitalia Supra-anal plate Basal and apical parts separated by transverse suture/furrow 1 1‡ 1¶ 0 0/1** 1 1§ 0/1† 0 **present in several genera, see text; §see text (Ronderos 1979; Amédégnato 1977); †present in Brasilacris, Staleochlora, and some Bactrophorinae; ‡Descamps (1966); ¶Pamphagus Cigliano et al. (2023). Epiphallus Epiphallus bridge-shaped, in one or two parts 1*00111-**11*modified in Tangana; **epiphallus in three parts (Eades, 1961: 167; Amédégnato 1977; Ronderos 1979). Ancorae present 0/1* 0 1 0 1** 1 0**/1§1 1 *incipient in Mazaea; **Dirsh (1956: 244, 247; Song & Mariño-Pérez 2013); §ancorae present in Aucacrinae (Ronderos 1979). Lophi present 1 0 0 1 1 1 1 1 1 Lophi pointed (not lobiform) 1 - - 1 1* 1 1 0 0 *predominantly (Otte 2014a). Lateral sclerites (oval sclerites) of epiphallus present 1 1** 0 1 1 1 1* 1 1 *Dirsh (1956, Plate 28A), Amédégnato (1977); Ronderos (1979); **homology uncertain (Dirsh 1956). Ectophallus Ectophallus fully sclerotized 1 1 1 1 1 0†/1**0* 0§/1 1 *Dirsh (1956: 247); **Atacamacridinae (Cigliano 1989a); † Tristirinae (Cigliano 1989a); §Bactrophorinae and Tropidacris. Valves of cingulum present 0/1* 0 0 0 0 0 0 0 1 *incipient in Mazaea, Barombia; see text (Figure 17) Rami of cingulum present 1 0 1 0* 1 1** 1 1 1 *Descamps (1968); **Cigliano (1989a). Zygoma of cingulum differentiated 0¶/1 0§ 1 1 1 0** 0†/1* 0‡/1 1 *Dirsh (1956: 247); “not clearly defined” (Eades 1961: 162) ** Cigliano (1989a); §Dirsh (1956); †Amédégnato (1977), Ronderos (1979); ‡e.g. Elaeochlorini (capsule-like cingulum); ¶diffuse in Rowellacris n. gen. Apodemes of cingulum differentiated 0*/1 1 1 1 1 0**/1§1 1 1 *variable in Rowellacris n. gen.; **Song & MariñoPérez (2013); §Atacamacridinae Cigliano (1989a: 53, Fig. 5). Apodemes of cingulum short 0/1 0 1 1 0 -/1* 1 1 0/1 *Cigliano (1989a: 53, fig. 5), inapplicable (Song & Mariño-Pérez 2013). Secondary apodemes of cingulum present 0/1* 0 0 0 0/1** 0 0 0 0 * Dirsh (1966: 100, 102); ** Dirsh (1961: 396, fig. 21); Brown (1962: fig. 4); Otte (2014a, figs 15, 17) ; see text. Arch sclerite present 1 1† 0‡ 0 0 0/1§ 0 0*/1** 1* *most prevalent state; **Diponthus (Pocco 2013); §see text; †Dirsh (1956); ‡zygoma connects direct to endophallus bilaterally (Dirsh 1956). Endophallus Endophallus with dorsal branch 0*00001000*?incipient in Ixalidium, Mazaea & Barombia; see text. Endophallus divided 1 1 1 1 0**/1§0/1† 0‡ 0* 0*/1† *mostly undivided, flexured, but divided in Hemiacridinae (Dirsh 1956);**e.g. Lentula (Dirsh 1956; §Brown 1970; ‡Dirsh 1961: 384); †polymorphic, see text. Endophallus with basal and apical sclerites articulated 1 0‡ 1 ? ‡ 0**/1§0/1† 0* 0* 0*/1§ *basal and apical valves with flexure; **endophallus undivided (Dirsh 1961); §valves separated in Eneremius (= Lithidium) (Dirsh 1961) and in Hemiacridinae (Dirsh 1956); †polymorphic, see text; ‡unclear. 535 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) (Lentulidae) (Brown 1962: fig.4; Otte 2014, fig.15) and in E.pusillum (Uvarov, 1925) (Dirsh 1961: 396, fig.21 (5); Otte 2014: fig.17). They do not appear to be present in other families of Acridoidea, but it is possible they may have been overlooked. The zygoma of cingulum was defined by Dirsh (1956: 228) as “a transverse dorsal part of the cingulum, connecting the apodemes and, in most cases, the cingulum itself with the apical valves of the penis”. It is shared by most Acridoidea and their sister group, the Pyrgomorphoidea. However, this character is an expression of a strongly sclerotized ectophallus, hence Cigliano (1989) stated that there is no zygoma in Tristiridae. However, the zygoma is present in all Ixalidiidae Hemp, Song& Ritchie n.fam., whether as a narrow transverse sclerite joining the cingular apodemes in Ixalidium, Mazaea and Barombia, or incorporated into a larger dorsal plate covering much of the endophallus in Rowellacris Ritchie& Hemp n.gen. In each case it connects ventrally to the arch of cingulum. The rami of cingulum, which generally cover the sides of a part of the endophallus, are present in all the families in Table13, except for the Pamphagodidae and Pyrgacrididae if the interpretation of Descamps (1968) is correct. The arch sclerite in Acridoidea, originally named “bridge of anterior phallotreme sclerites” (Snodgrass 1935), was subsequently named “arch of dorsal valves” and “arch of aedeagus” by Roberts (1941: 241), who considered it “a development from the aedeagal valves or endophallic membrane rather than from the zygoma of the cingulum”. Both Dirsh (1956: 225) and Amédégnato (1976: 7-8, Plate II, Figs12-15) subsequently described and illustrated the “arch of cingulum” as a sclerite of ectophallic origin connecting the cingulum and the endophallic sclerites. Amédégnato (op. cit.) stated that in groups with a well-developed aedeagus the arch could either fuse with the dorsal valves of endophallic origin or alternatively it could give rise to genuine “valves of cingulum”. Eades (1962: 6-7) noted that “homologies of the arch, bridge and dorsal aedeagal sclerites have never been suggested except by speculation”, before speculating that in Dericorythinae Jacobson & Bianchi, 1905 (now Dericorythidae), which he considered to be intermediate between Ommexechidae and Romaleidae and the Acrididae, the arch had initially developed as a pair of sclerites arising from the phallotreme membrane adjoining the “primitive” single pair of (ventral) aedeagal sclerites and extending dorsad to fuse with the ectophallic membrane at the rear of the cingulum, giving rise to a dorsal pair of aedeagal valves in some cases and subsequently becoming fused into a single structure bridging the ventral sclerites. Eades (1962: 6-7) indicated his belief that the arch in Dericorythidae was homologous with that in Acrididae, but he later (Eades 2000:184) expressed the view that it is a pseudoarch “not homologous with the true arch found in Charilaidae [= Pamphagodidae] and Acrididae”. However, Song etal. (2018: 4) considered that the arch sclerite is homoplasious within the Acridoidea, having apparently evolved separately in Pamphagodidae and Acrididae. Presence or absence of the arch sclerite is difficult to establish and requires dissection of the phallic complex (Song etal. 2018: 13). Uvarov& Dirsh (1961: 153) argued that the arch was absent in several genera of Acrididae, “appearing sometimes only as a slightly sclerotised part of the ectophallic membrane”. The uncertainty derives from the variability in the degree of sclerotization of the structure in different genera and the subjectivity of a presence / absence decision. Song (2004) demonstrated that in Schistocerca Stål, 1873 the arch sclerite develops during the adult stage, being largely undeveloped at fledging, and only reaching its full size before sexual maturity. He suggested that this may have led to S.braziliensis Characters (described state = 1 unless otherwise stated) Ixalidiidae n. fam. Pamphagodidae Pamphagidae Pyrgacrididae Lentulidae Tristiridae Ommexechidae Romaleidae Acrididae Notes and references Gonopore present 0/1* 0 0 1 1 1 1 1 1 *see text. Ejaculatory sac ventral to endophallus -*/1 1 1 1 1 1 1 1 1 *See text. Spermatophore sac dorsal to ventral endophallic sclerites 1 1 1 1 1 1 0 0 1*/0 *“transverse” (Song & Mariño-Pérez 2013). Gonopore process present ?1* 1§ 1§ 1§ 1** 1** 1** 1 1 **if the hypothesis of Eades (1961) is correct for all families with spermatophore sac situated dorsal to the endophallus; see Discussion; **Eades (1961); §Eades (2000). Dorsal endophallic aedeagal sclerite present 0 0 0 0 0 0 0 0/1* 0 *most prevalent state = 1. No of monomorphic character states fully congruent with Ixalidiidae n. fam. 14 9 9 10 10 9 8 6 9 Table 13. — Continuation. 536 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. Dirsh, 1974 being defined on the basis of immature material (Dirsh 1974: 166). Nonetheless, the presence of the arch of cingulum connecting the zygoma to the apical valves of the endophallus in most Acrididae and its absence in most Romaleidae has been considered of importance in establishing relationships (Amédégnato 1976, 1977; Eades 2000). In the absence of any other synapomorphy of the Acrididae, Song etal. (2018: 13) concluded that “the fact that we have recovered the monophyletic Acrididae strongly suggests that this obscure genital character [the arch of cingulum] may indeed be a synapomorphy for the family”. In Melanoplus rotundipennis (Scudder, 1878) (Acrididae) Woller& Song (2017: 345, 351, 354) showed that the ‘arch of aedeagus’, arising from the dorsal valves and inserted into the lower region of the zygoma, provides through the zygoma a point of articulation and structural support for the aedeagus during mating. Either a single arch sclerite or a pair of sclerites is present in all genera included within the family Ixalidiidae Hemp, Song& Ritchie n.fam. In the genus Rowellacris Ritchie& Hemp n.gen. the enlarged and expanded arch sclerite also appears to function as a stiffener and spacer that maintains the gap between the cingulum and the endophallus, otherwise usually connected only by membranes. The presence in the aedeagus of sclerites of ectophallic origin or dorsal valves of the cingulum (Amédégnato 1976), together with an arch sclerite, was regarded by Song& Mariño-Pérez (2013) as an autapomorphy of the Acrididae, although cingular valves and an arch of ectophallic origin are also present in Diponthus (Romaleini, Pictet & Saussure, 1887) (Uvarov& Dirsh 1961; Amédégnato 1976: 8; Pocco etal. 2023). Eades (1962: 6-7) stated that in Romaleidae and Ommexechidae the arch was only present when a dorsal pair of aedeagal sclerites were also present. In the present study of the members of the Ixalidiidae Hemp, Song& Ritchie n.fam. a bifurcated horn-like posterior medial outgrowth of the cingular arch, possibly representing incipient valves of cingulum (C.H. Rowell, personal communication, June 2020), has been found appressed to the dorsal surface of the posterior section of the endophallus in Mazaea (Fig.18A, B). This structure was previously illustrated, but not commented on, in Barombia by Dirsh (1966, fig.40) whose own dissected specimen has been photographed (Fig.18C). Posterior medial dorsal projections of the zygoma in Namatettix Brown, 1970, Atopotettix Brown, 1970 (Brown 1970: 495, 505) and Shelfordites Karny, 1910 (Brown 1967: figs1b,1c) (Lentulidae), that were considered by Brown as dorsal or cingular valves, may or may not be homologous with the structures found in Mazaea and Barombia. The term “pseudoarch” was originally coined by Akbar (1966: 77) to describe the arch structure found in Pyrgomorphidae (specifically in Poekilocerus pictus Audinet-Serville, 1831). Akbar defined the pseudoarch as “a small transverse sclerite … developed in the distal part of the central membrane close to the base of the suprarami. It forms an inflection laterally, and carries dorsally a pair of valves of the cingulum”. Akbar’s drawings show that his pseudoarch was attached dorsally to the central membrane posterior to the zygoma rather than to the zygoma itself. In studies of the Tristiridae (Amédégnato 1977: 49; Cigliano 1989a, b) the term pseudoarch has been used to describe a sclerite, said to be of uncertain origin, attaching dorsally to the rear edge of the cingulum and ventrally to the endophallus in the same position as occurs with the arch of cingulum in Acrididae, but in the absence of a zygoma and dorsal valves of cingulum in the aedeagus. This arch structure may be absent, reduced or prominent (Cigliano 1989a) and is of significance in defining the subclades of a “Tristira generic group” (= tribe Tristirini) within the family. It is absent in those genera which lack an aedeagus (= without development of distal portion of endophallic sclerites, Cigliano 1989b), but well-developed in several genera, including Moluchacris Rehn, 1942, Peplacris Rehn, 1942 (Fig.23A), Punacris Rehn, 1942, Crites Rehn, 1942, Paracrites Rehn, 1942, Incacris Rehn, 1942, and with incipient development in Bufonacris Walker, 1871 (Fig.23E), Tristira Brunner von Wattenwyl, 1900 and Circacris Ronderos& Cigliano, 1989. It is thus apparent that similar arch structures joining the cingulum to the aedeagus occur in different families of Acridomorpha, but there is no agreement as to their homologies or the appropriate terminology with which to describe them. A comparative morphological study of these arch structures would be a useful contribution to understanding the evolution of the genitalia in Acridomorpha. Endophallus Amédégnato (1976, 1977) considered the sclerotised endophallus to be constituted in three sections, anterior, middle and posterior. The anterior part consists of the paired endophallic apodemes; the middle part is a pair of sclerites, in Acrididae called the lateral plates of Roberts (1941), which strengthen and support the walls of the ejaculatory and spermatophore sacs, while the posterior part (which may be present or absent) participates in the formation of an aedeagus, where this A T = 24°C T = 24°C 1 s T = c. 24°C B C Fig. 20 . — Oscillograms of single echemes of species of Ixalidiidae Hemp, Song & Ritchie n. fam.: A, Rowellacris Ritchie & Hemp n. gen. sp. (Lutindi, W Usambara); B, Tangana asymmetrica Ramme, 1929 (Nguru Mts); C, Tangana sp. (Tanzanian Coast, Zanzibar). 537 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) is present. Between the middle part and the posterior part of the endophallus there may be a fracture, creating a division. Possession of a divided endophallus groups the Ixalidiidae Hemp, Song& Ritchie n.fam. with the Pamphagodidae and Pamphagidae together with the Pyrgacrididae, Lithidiidae, some Tristiridae (Fig.6) and some Lentulidae (see below). Other genera of Lentulidae (Lentula Stål, 1878, Eremidium Karsch, 1896) have an undivided endophallus (Dirsh 1956: 244), while in many Acrididae the endophallus is flexured, but without a break. Song& Mariño-Pérez (2013: table3) considered the flexure as equivalent to a division, but that interpretation is not followed here, as explained below. The presence of a divided endophallus with basal and apical pairs of sclerites articulated rather than completely disconnected, was considered by Song& Mariño-Pérez (2013: 253) to group the Tristiridae, Lentulidae, Pamphagidae, Ommexechidae, Romaleidae and Acrididae. However their character state “endophallus articulated” actually combined two distinct types of linkage between basal and apical sclerites of the endophallus. Firstly there may be a visible disjunction or fracture (Amédégnato 1976), forming a “hinge”, as noted by Song& Mariño-Pérez (op. cit.) or, alternatively, there may be a spring-like thinning of the endophallus, the sigmoid flexure (Roberts 1941; Dirsh 1956, 1961), which may achieve A X X X X X X X X E HIJ F C GD B Fig. 21. — Examples of C-banding (A, D, H), active NOR visualized by silver staining (B, E, I), and fluorescence in situ hybridization (FISH) with both 18S rDNA (green) and telomeric DNA (red) probes (C, F, G, J) in male chromosomes of Ixalidium sjostedti (A-C), Rowellacris usambarica (D-G) and Tangana asymmetrica (Kimboza) (H-J); diakinesis/metaphase I (A-C, E, G, H-J) and spermatogonial metaphase (D, F); black arrows show NORs/NOR located in the medium-sized bivalents/bivalent (B, E, I), white arrows point the chromosomal location of rDNA clusters of one bivalent/pair; black arrowheads show interstitially located Cband on the sex chromosome (H). X, sex chromosome. Scale bar: 10 µm. 538 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. the same function without creating a disjunction. This is the condition in many Romaleidae and Acrididae, including Ommatolampidinae, e.g. Eujivarus Bruner, 1911 and Eugenacris Descamps& Amedegnato, 1972 (Amédégnato 1976: figs26, 28), Oedipodinae Walker, 1871, e.g. Oedaleus Fieber, 1853 and Gastrimargus Saussure, 1884 (Ritchie 1981, 1982), Acridinae (Popov etal. 2019) and Catantopinae (e.g. Rowell etal. 2018). Conflating these two forms of endophallic linkage in the character matrix may potentially obscure significant differences. In most members of the acridid subfamily Hemiacridinae, the endophallus is completely separated into basal and apical parts (Dirsh 1956: 155). In Ixalidiidae Hemp, Song& Ritchie n.fam. the divided endophallus is hinged, with separate basal and apical parts, distinct but closely appressed anterior to the arch sclerite(s). The medial sclerites of the endophallus are dorso-ventrally flattened anteriorly and attenuated in Mazaea (Fig.7H), Barombia, Eubocoana and Ixalidium continuous with the basal sclerites (Fig.11D). In Ixalidium the conjoined medial sclerites are evidently flexible enough to allow the apical section of the endophallus to be folded upwards by as much as 30°, compressing the spermatophore sac. However, in Rowellacris Ritchie& Hemp n.gen. (Fig.15H) and Tangana (Fig.17T) the medial sclerites have been reduced almost completely, so that the hinge occurs between the anterior basal section (the endophallic apodemes) and the apical sclerites which, together with an ectophallic sheath, form the aedeagus. The ejaculatory sac is normally ventral to the basal valves of the endophallus in the families of Acridoidea listed in Table13, but the sac is apparently vestigial in Rowellacris Ritchie& Hemp n.gen., in which the ejaculatory duct is only minimally widened before becoming internalized within the fused basal valves of the endophallus. In Tangana, the ejaculatory duct also passes caudad within the fused basal valves of the endophallus to the dorsally-positioned spermatophore sac. However, there appears to be a small sac, appended to the ejaculatory duct well forward of its point of entry into the basal valves of the endophallus, which is not always preserved during dissection of the genitalia. This may represent the reduced ejaculatory sac. The presence of a gonopore, defined as a constriction between the ejaculatory sac and the spermatophore sac (Snodgrass 1935), was regarded by Song& Mariño-Pérez (2013) as distinguishing the Acridoidea from all other superfamilies. However, in Ixalidiidae Hemp, Song& Ritchie n.fam., while the ejaculatory sac is constricted at its junction with the ejaculatory duct in Ixalidium, Mazaea and Barombia, in both Rowellacris Ritchie& Hemp n.gen. and Tangana, the presence of a gonopore is currently inferred rather than observed, due to the vestigial condition of the ejaculatory sac described above. The gonopore processes are pointed postero-ventral protrusions of the endophallic apodemes (basal valves of the endophallus), constricting the gonopore in Acridoidea. Though initially regarded as absent in Pyrgomorphidae (Kevan etal. 1969: 185, 231), they were subsequently identified with the endophallic sclerites (Eades& Kevan 1974: 250). They were scored by Song& Mariño-Pérez (2013, table3) in their character matrix as present only in the Acrididae and Romaleidae and absent from the Tristiridae and Ommexechidae, so that when morphological characters were superimposed onto their mitochondrial genome tree (op. cit., fig.5B) the presence of gonopore processes was shown as a synapomorphy of the Acrididae, Ommexechidae and Romaleidae, that had subsequently been secondarily lost in the Ommexechidae. However, Eades (1961: 162) had previously illustrated the presence of gonopore processes in the Ommexechinae, in contradiction to Dirsh (1956: 247), confirming the synapomorphy across all three families. According to the current paradigm in which the ventral endophallic sclerites of Pyrgomorphidae, Lentulidae and Tristiridae are considered to be homologous with the gonopore processes of Acrididae, gonopore processes must, by definition, be present in all those families, making this a synapomorphy that also includes Lentulidae and Tristiridae. Prior to their synonymy with Lentulidae, the medial sclerites of the endophallus in Lithidiidae were also identified as enlarged gonopore processes (Eades 2000: 194). Table13 therefore reflects this probable state. Given the apparent sister status of Ixalidiidae Hemp, Song& Ritchie n.fam. to Tristiridae in the phylogenetic tree derived from the mitochondrial genome (Fig.1), it is likely that the medial sclerites of the endophallus in Ixalidiidae Hemp, Song& Ritchie n.fam. are also derived from enlarged gonopore processes and thus homologous with the ventral branch of the endophallus in Tristiridae. Eades (2000: 185) describes additional small sclerites appended to the gonopore processes in Ommexechidae and some other acridoids which he termed antero-ventral flanges of the endophallic sclerite. In Tristiridae Cigliano (1989b: 56) noted that “a projection (gonopore process?) arises ventrally from the anterior region, the development of which is variable. This projection is barely hinted at in Elasmoderini and Atacamacridinae. In Tropidostethini it presents a greater development, joining the dorsal endophallic sclerite through a zone of lesser sclerification. In Tristirinae it is prominent”. If the original gonopore processes have become the ventral endophallic sclerites in Tristiridae, as proposed by Eades (1962), then perhaps these ventral projections of the gonopore processes (Fig.23B) represent the antero-ventral flanges of Eades (2000). In Ixalidiidae Hemp, Song& Ritchie n.fam. these antero-ventral flanges of the endophallus are either absent or incipient (in a medial position in Mazaea and Ixalidium (Figs7G; 10C). The spermatophore sac is positioned distal to the ejaculatory sac in Acridoidea. It is placed dorsally in relation to the endophallus in Pamphagodidae, Pamphagidae, Pyrgacrididae, Lentulidae and in Ixalidiidae Hemp, Song& Ritchie n.fam. However, it is situated ventrally, below the endophallus, in Ommexechidae and Romaleidae. In Tristiridae the spermatophore sac is situated between the dorsal and ventral branches of the endophallic sclerites and therefore in a dorsal position relative to the ventral endophallic sclerites. Song& MariñoPérez (2013: 250) scored the spermatophore sac in Acrididae, uniquely, as “transverse” rather than ventral since part of the sac is situated above the flexure of the endophallus in 539 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) Acrididae. If it were regarded as ventral, this character state would be an uncontroverted synapomorphy of this terminal clade of the Acridoidea. A revised character tablefor the Acridoidea The basal families of the Acridoidea clade are the Pamphagidae and Pamphagodidae which are consistently recovered as sister clades (Leavitt etal. 2013; Song etal. 2015, 2020 and Fig.1), Both families lack the bridge-shaped epiphallus bearing lophi that is shared by the Pyrgacrididae and the remaining eight families (including Ixalidiidae Hemp, Song& Ritchie n.fam.) of the core clade of Acridoidea. Accordingly, although they have been included in Table13, they are not considered in depth in this study. Table13 uses a traffic light approach to indicate the congruence of character states between Ixalidiidae Hemp, Song& Ritchie n.fam. and the other acridoid families, with green for full congruence, amber for partial congruence and red for incongruence. Most of the characters defined by Song& Mariño-Pérez (2013) have been used, with some modification and augmentation, including the addition of characters of the male supra-anal plate (epiproct) and the female genitalia and the omission of a few characters which have identical character states for all families, or which appear to be inapplicable, unclear, or overly subjective. An extensive survey of relevant literature indicates that some of the male genitalic characters found to be monomorphic in the exemplar taxa studied by Song& Mariño-Pérez (2013) AB F C D E Fig. 22. — Epiphallus, dorsal view: A, B, Tristiridae Rehn, 1906: A, Eremopachys bergi Brancsik, 1901, Chile B, Moluchacris cinerascens (Philippi), Chile, after Song & Mariño-Pérez (2013, fig 4H); C-F, Ixalidiidae n. fam. Hemp, Song & Ritchie: C, Mazaea granulosa, Nigeria; D, Rowellacris usambarica n. comb., Tanzania; E, Ixalidium haematoscelis, Kenya; F, Tangana asymmetrica, Tanzania. Scale bars: B, F, 0.5 mm; C-E, 0.2 mm; A, not to scale. 540 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. are in reality polymorphic at family level. In Table13, out of a total of 24genital characters analyzed, just 14 characters are found to be unambiguously monomorphic for the Ixalidiidae Hemp, Song& Ritchie n.fam. Among those, the largest number of monomorphic character states shared with another family is 10 with the Lentulidae and Pyrgacrididae, followed by nine with Pamphagodidae, Pamphagidae, Tristiridae and Acrididae, eight with Ommexechidae, and six with Romaleidae. The interpretation of individual characters and their significance and application in some of the core families of Acridoidea are further examined in the Discussion section. bioacoustics Up to now, in species of Ixalidiidae Hemp, Song& Ritchie n.fam., no sound producing organs or specialized modified structures have been found. Nevertheless, when kept in captivity, males of three species of Rowellacris Ritchie& Hemp n.gen. (R. obscuripes n. comb., R.usambarica n. comb., R.sp. (Lutindi W Usambara)) and two putative Tangana species (T.asymmetrica, Tangana sp. (coastal Tanzania and Kenya, Zanzibar)), as well as females (documented as Tangana sp. only), displayed the ability to generate relatively loud rhythmic sounds through drumming/tapping with their hind knees on the substrate. The observed echemes, consisting of 9-27 impacts with varying rates (12-16 Hz for Rowellacris Ritchie& Hemp n.gen. spp., Tangana asymmetrica, and 35-38 Hz for Tanganasp. (T = 23-27°C; Fig.20), were produced at irregular intervals. Both legs were moved largely in phase. Females were observed to either respond to male signals or spontaneously produce similar signals. cytotaxonoMy All three examined genera, namely Ixalidium, Rowellacris Ritchie& Hemp n.gen., and Tangana (Fig.23A-J), exhibited a diploid chromosome number of 2n = 25 in males and 2n = 26 in females, with a sex chromosome system of X0 in males and XX in females. The autosomes displayed a gradual reduction in size, while the sex chromosome (X) was acrocentric. During male spermatogonial mitosis and meiosis, C-positive blocks were consistently observed in the paracentromeric region of all chromosomes, with interstitial C heterochromatin bands present in the sex chromosome of Tangana asymmetrica (Fig.21A, D, H). Silver staining revealed the presence of two active nucleolar organizer regions (NORs) per haploid genome in I.sjostedti and one in R.usambarica n. comb. and T.asymmetrica. These NORs were situated in the paracentromeric region of two or one medium-sized bivalent, respectively (Fig.21B, E, I). In addition, a substantial cluster of 18S rDNA was detected during mitotic metaphase or within bivalents from diakinesis to metaphase I, coinciding with the active NORs identified by Ag-NOR staining (Fig.21C, F, G, J). To further probe the chromosomal structure, fluorescence in situ hybridization (FISH) using the (TTAGG)n probe (tDNA-FISH) was performed on spermatogonial mitoses and/or spermatocyte nuclei during meiosis, specifically at diakinesis and metaphase I. In all analyzed taxa, signals were consistently detected at the distal ends of each chromosome. Notably, the tDNA-FISH signals on chromosomes of T.asymmetrica appeared notably stronger compared to those observed in the other species of Ixalidium and Rowellacris Ritchie& Hemp n.gen. (Fig.21J). DISCUSSION bioacoustics The findings of sound production in Ixalidiidae Hemp, Song& Ritchie n.fam. raise intriguing questions about the adaptive significance and communication purposes of this behaviour. The animals produced the sounds by drumming with their hind legs on the substrate, a form of sound production known as percussion (Baker& Chesmore 2020). Percussion is the generation of noises by the impact between parts of the body and the substrate, and it is widespread in the animal kingdom. Notably, it is relatively rare and/or poorly documented in Acridoidea, with detailed descriptions limited to Centroamerican proctolabine Drymophilacris bimaculata (Rehn, 1905) and the East African catantopine Sauracris crypta Popov, 1959 (Ritchie 1988) among acridids. Understanding the evolutionary and ecological factors influencing the development of such communication strategies in Ixalidiidae Hemp, Song& Ritchie n.fam. becomes crucial. The signals most likely contribute to the locatability of mating partners, although comprehensive studies on the informational content of these signals are currently lacking. The purpose of percussion in Orthoptera appears to be primarily for the production of substrate vibrations rather than airborne sounds. Such signals are easily overlooked or unheard, as emphasized by Ingrisch& Rentz (2009), stating that “Many catantopines produce no audible sound, but some perform drumming actions on their host plants with the hind legs, thereby announcing the presence of a mate without the need for acoustical amplification” (Baker& Chesmore 2020). The lack of specialized sound-producing organs in Ixalidiidae Hemp, Song& Ritchie n.fam. suggests a potentially unconventional route for acoustic communication within the family. The observed rhythmic patterns in sound production, along with the noted variability in rates among different species, open avenues for investigating the specificity and significance of these signals (Baker& Chesmore 2020). Consideration should be given to the environmental context, as suggested in the papers of Pollack etal. (2016) and Baker& Chesmore (2020), emphasizing the potential role of substrate characteristics in shaping the spectral patterns of these drumming signals. Pollack etal. (2016) assume that “drumming produces broadband “noisy” signals that are most often associated with heterogeneous substrates, where the filtering characteristics of the substrate are unpredictable”. Under these conditions, only the temporal pattern of the sound may carry the intended information (Cocroft etal. 2014). 541 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) The potential role of female responses to male signals and the spontaneous sound production by females warrant further investigation. The study highlights the need for comprehensive research to decipher the specific information carried by these signals and their importance in mate attraction and communication within the Ixalidiidae Hemp, Song& Ritchie n.fam. cytogenetics A comparative cytogenetic investigation of three genera of African Ixalidiidae Hemp, Song& Ritchie n.fam. offers novel insights into karyotype evolution among grasshoppers. The results showed that the male diploid chromosome number of one Ixalidium, two Rowellacris Ritchie& Hemp n.gen., and one Tangana species was 2n = 25 (24 + X0). Recent research by Husemann etal. (2022) confirmed the widely held belief that the karyotypes of Acrididae grasshoppers are very stable, with a male ancestral chromosome number of 2n = 23 (22 + X0), found in almost three-quarters of the over 1000 chromosome records studied across 339 genera. So far, a karyotype with 25 chromosomes has been found only in one species, Oedipoda schochii Brunner von Wattenwyl, 1884, collected in Turkey (Türkoglu& Koca 2002). Nevertheless, information regarding chromosome numbers in Tristiridae species, the closest family to Ixalidiidae Hemp, Song& Ritchie n.fam., remains limited. In this family, six South American species from the genera Bufonacris, Elasmoderus, Elysiacris, Moluchacris, Peplacris, and Tripidostethus have different numbers of male chromosomes, equaling 2n = 23, 2n = 21, and 2n = 19 (Mesa etal. 1982). Explanation of the presence of a chromosome number higher in Ixalidiidae Hemp, Song& Ritchie n.fam. (2n = 25) than ancestral or plesiomorphic (2n = 23) at present seems difficult, but it represents a cytogenetically distinct group. To explore chromosomal markers and compare cytogenetic traits within African Acrididoidea, we conducted an exhaustive cytogenetic analysis employing both classical methods (C-banding technique, NOR Ag-staining) and molecular techniques (FISH using rDNA and tDNA). Recent studies on Acrididae grasshoppers have increasingly combined these methods for comparative mapping, yielding valuable insights into genome evolution in this taxonomic group (e.g., Jetybaev etal. 2012; Grzywacz etal. 2018, 2019). This study presents, for the first time, chromosomal data for African Ixalidiidae Hemp, Song& Ritchie n.fam., revealing distinctions among species within Ixalidium, Rowellacris Ritchie& Hemp n.gen., and Tangana. We identified blocks of constitutive heterochromatin in the paracentromeric regions of autosomes and the X chromosome, with additional interstitial occurrences in the sex chromosome of Tangana. Our mapping of 18S rDNA genes in these species, which share the same chromosome number and are situated exclusively in the paracentromeric region, disclosed variations in the number of these genes between Rowellacris Ritchie& Hemp n.gen. and Ixalidium. In I.sjostedti, a single bivalent featured the rDNA cluster, while Rowellacris sp., R.usambarica n. comb., and Tangana asymmetrica displayed two bivalents. Physical mapping of rDNA sequences and heterochromatin in orthopterans provides valuable additional markers for deciphering chromosomal organization, distinguishing species or genera, and discerning phylogenetic relationships (e.g., Grzywacz etal. 2011, 2014; Warchałowska-Śliwa etal. 2011, 2013). The number and variability of major 18S rDNA can vary among closely related species and even within species among grasshoppers (e.g., Cabrero& Camacho 2008; Grzywacz etal. 2019) or tettigoniids (e.g., Warchałowska-Śliwa etal. 2013, 2021). In all three genera examined in this study, our FISH analysis of 18S rDNA loci consistently corresponded with the active NORs identified via Ag-NOR staining. These NORs were consistently located in the paracentromeric region of the medium autosome, in agreement with prior research in other orthopterans (Grzywacz etal. 2014). Furthermore, the detection of (TTAGG)n repeats at the chromosome ends in the studied species aligns with previous findings in other Orthoptera, including certain grasshoppers and tettigoniids (Grzywacz etal. 2011; Jetybaev etal. 2012; WarchałowskaŚliwa etal. 2013). genital Morphology in soMe core faMilies of acridoidea Lentulidae The only genitalic character defining the Lentulidae clade of the Acridoidea phylogenetic tree presented by Song& MariñoPérez (2013) was the possession of an undivided endophallus, based on dissection of a member of the type genus, Lentula Stål, 1878 (op. cit: 247) and figures representing Lentula, Eremidium and Gymnidium Karsch, 1896 in Dirsh (1956) which support this definition. However, a substantial number of genera currently included in the Lentulidae have a divided endophallus, including Afrotettix Brown, 1970, Atopotettix Brown, 1970, Dirshidium Brown, 1970 (Brown, 1970) and Leatettix Dirsh, 1956 (Shelforditinae) (Otte 2014a). Dirsh (1975: 140) erected the subfamily Shelforditinae for Shel - fordites Karny, 1910 within his family Catantopidae, a family concept maintained by Li etal. (2011) but which has not been validated by recent synoptic phylogenetic studies (e.g. Song etal. 2018). Ritchie (1982a: 179) postulated a possible evolutionary sequence from the simple rod-like endophallus still found in Lentula or Altiusambilla Jago, 1981, via the attenuated (‘flexured’) endophallus of Shelfordites to the divided endophallus of Leatettix, Calviniacris Dirsh, 1956, Uvarovidium Dirsh, 1956 and Afrotettix, Atopotettix and Dirshidium, and ultimately the extreme condition of apical valve reduction found in Eneremius Saussure, 1888. He proposed redefining Dirsh’s Shelforditinae (within the Lentulidae) as lacking a cingular arch and cingular valves and possessing an attenuated (flexured) or divided endophallus, cingular rami with lateral expansions and cingular apodemes which are elongated, parallel and close together. Otte (1995) incorrectly attributed the subfamily Shelforditinae to Ritchie (1982b), rather than to Dirsh (1975). This error has been repeated in several websites and papers (e.g. Cigliano etal. 2022; Matenaar etal. 2016). Matenaar etal. (2016) provided a partial phylogeny for the South African Lentulidae based on two mitochondrial genes, 542 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. which indicates that the two currently recognised subfamilies Lentulinae and Shelforditinae are both paraphyletic and in need of taxonomic revision and molecular phylogenetic studies. They noted that Devylderia Sjöstedt, 1923 (currently Lentulinae) clusters with Uvarovidium and Leatettix (Shelforditinae). However, notwithstanding the misplacement of Devylderia, their dataset indicated two major radiations of species, corresponding to the two recognised subfamilies. Hemp etal. (2020) recovered the same two subfamily clades, showing the major Miocene radiation of Lentulinae into Eastern Africa. Until recently the Lithidiidae were a small family of deserticolous grasshoppers from Namibia. They included Lithidium Uvarov, 1925, Lithidiopsis Dirsh, 1956, Eneremius and Microtmethis Karny, 1910 (the only winged genus), all of which (including the winged species Microtmethis kuthyi Karny, 1910) share with the Lentulidae the synapomorphy of complete absence of the tympanum (Dirsh 1961). The family was elevated from subfamily status within the Acrididae by Eades (2000) in a single paragraph of text largely based on one drawing of the genitalia of Lithidium pusillum (Uvarov, 1925) by Dirsh (1975: fig.42), with a comment that the family has close affinities with Lentulidae and Pamphagidae. In Dirsh’s Lithidiinae, the apical sclerites of the endophallus were thin and elongated, fully disconnected from the basal valves and covered by an ectophallic sheath (Dirsh 1961: 395-396). The divided endophallus was originally thought to separate them from Lentulidae which had previously been characterised as sharing a continuous, undivided endophallus (Dirsh 1956: 244). However, this character state is no longer present in many genera currently assigned to Lentulidae (see above). Otte (2014) synonymised Lithidium with Eneremius and transferred Lithidiopsis to the Lentulidae, on the grounds that it appeared related to Leatettix (Shelforditinae), although the molecular phylogeny presented here (Fig.1) places Lithidiopsis close to Lentula (Lentulinae). Most recently Otte (2024) has finally synonymised Lithidiidae with Lentulidae, by transferring Eneremius. Otte (2024) excluded Microtmethis from Lentulidae on the grounds that it possesses forewings, unlike all Lentulidae. Its true phylogenetic position remains unknown. Otte (2014, 2014a, 2024) has provided greyscale images of the phallic complex for all genera, but these are not sufficiently sharply detailed to establish clear distinctions between genera in the absence of any accompanying commentary on comparative genital morphology. There is clearly a need for a wider molecular phylogenetic and morphotaxonomic study of all the genera currently assigned to the Lentulidae. Pyrgacrididae The genital morphology of this family is still poorly understood and homologies with other families are unclear. It has been considered a transitional form between Pyrgomorphoidea and Acridoidea (Eades 2000), but this view is no longer tenable. The entries in Table13 for this group are based on the descriptions of the morphology of Pyrgacris relictus Descamps, 1968 and P.descampsi Kevan, 1976 by Descamps (1968) and Hugel (2005) which sometimes conflict with character states reported by Song& Mariño-Pérez (2013: 248, fig.3). It is not clear from published sources whether the basal and apical endophallic valves are fully disconnected or are hinged in Pyrgacris. An arch sclerite appears to be absent in this family, judging from the highly diagrammatic drawings by Descamps (1968), but he did not explicitly state this. In the current phylogenetic tree (Fig.1) the Pyrgacrididae are a sister group basal to the remaining core families of the Acridoidea clade (excluding Lentulidae). Tristiridae The sister relationship between the Ixalidiidae Hemp, Song& Ritchie n.fam. and the Tristiridae clade revealed by analysis of the mitochondrial genome (Fig.1) was unexpected. The Tristiridae are a small group of grasshoppers of small to medium size with an Andean/Patagonian distribution across southern and western parts of South America (Peru, Argentina and Chile). They have been divided into two subfamilies, the monotypic Atacamacridinae Carbonell & Mesa, 1972 and the Tristirinae with 16 genera and 24species (Cigliano 1989b), with diverse external morphology and ranging from fullywinged, through brachypterous forms to apterous (Cigliano 1989b). The general habitus of some genera of Tristiridae (e.g. Incacris, Paracrites, Moluchacris, Peplacris, or Tropidostethus) is strongly convergent with that of the Ixalidiidae Hemp, Song& Ritchie n.fam., with the frons oblique and the fastigium of vertex strongly projecting (Fig.19A, B). Even elements of the colour patterning, such as black lateral markings on the thoracic pleura and abdominal tergites may be closely similar. The lower basal lobe of the hind femur may project beyond the upper lobe (Eades& Kevan 1974: 260), a feature characteristic of Pyrgomorphidae, or it may be as long as or shorter than the upper lobe, as shown by accurate drawings (Cigliano 1989b), sometimes varying even within a single genus. In Ixalidiidae Hemp, Song& Ritchie n.fam. the upper basal lobe of the hind femur is always longer than the lower. The external apical spine of the hind tibia is present in most Tristirinae, though lacking in Incacris, Crites and Paracrites and of variable occurrence in Tebacris and Bufonacris, sometimes varying within a single species or bilaterally within one individual. It is absent in the Atacamacridinae (Carbonell& Mesa 1972). All Tristiridae share a relatively simple female spermatheca with either a single apical ampulla only, or with an additional adjoining short appendix. Differences between the male genitalia of Tristiridae and those of Ixalidiidae Hemp, Song& Ritchie n.fam. are briefly summarised below. Epiphallus (Fig.22): In Tristiridae the ancorae are usually well developed (Fig.22A, B), in contrast to their absence in most Ixalidiidae Hemp, Song& Ritchie n.fam. (Fig.22CF). However, in Mazaea (Ixalidiidae Hemp, Song& Ritchie n.fam.) incipient ancorae are present in the same location as those seen in some tristirids (Fig.22C). There is no externolateral spur near the base of the lophi of Tristiridae as there is in most Ixalidiidae Hemp, Song& Ritchie n.fam. However, circular sensory pores in the medial area of the bridge, possibly campaniform or coeloconic sensilla, like those seen in Ixalidiidae Hemp, Song& Ritchie n.fam., can be observed in some tristirid species that have a wide bridge (Tropidostethus 543 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) angusticollis (Blanchard, 1851), Eremopachys bergi Brancsik, 1901 (Fig.22A), Tebacris nigrisoma Cigliano, 1989). Ectophallus: In Tristirinae (the most diverse subfamily) the cingulum is usually sclerotized proximally and membranous caudally, with the development of a basal (dorsal) fold and usually of lateral sclerites. The apodemes of cingulum are proximally broad and plate-like, quite different in appearance to those observed in Ixalidiidae Hemp, Song& Ritchie n.fam. and considered by Kevan etal. (1969) as not homologous with the cingular apodemes of Acrididae. However, in the monotypic Atacamacridinae Cigliano (1989b) reported narrower apodemes of acridid type. The supplementary pair of delicate narrow apodemes of the cingulum and lateral spurs found in Ixalidium and Mazaea do not occur in Tristiridae. The rami of cingulum are of variable development and there is no evident development of a sclerotized zygoma (Cigliano, 1989). Endophallus: The Tristiridae have been considered a monophyletic group of genera (Cigliano 1989a, b; Cigliano& Lange 2000) clearly distinguished morphologically from other families within the Acridoidea (Amédégnato 1977: 50; CigliA C B Ac Sps Ejs Gp VEP DEP MDEP BPDEP DPVEP Aed D F E Fig. 23. — Endophallic sclerites, Tristiridae: A, B, Peplacris recutita Rehn, 1942; C, D, Eremopachys bergi Brancsik, 1901; E, F, Bufonacris bruchii Brancsik, 1901: A-C, E, lateral; D, F, dorsal. 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Zootaxa 4969 (1): 101118. https://doi.org/10.11646/zootaxa.4969.1.5 Zhang c., Mao b., wang h., dai l., huang y., chen Z. & h uang J. 2023.— The Complete Mitogenomes of Three Grasshopper Species with Special Notes on the Phylogenetic Positions of Some Related Genera. Insects 2023, 14, 85. https:// doi.org/10.3390/insects14010085 Submitted on4August 2024; accepted on 26March 2025; published on 3 October 2025. 552 ZOOSYSTEMA • 2025 • 47 (24) Hemp C. et al. APPENDIX appeNdix 1. — Vouchers for taxa of Acridoidea included in the molecular phylogeny (Figure 1) by family, subfamily, genus and species. Family Subfamily Genus Species Voucher Number mtDNA 18S 28S Acridoidea Acrididae Acridinae Acrida willemsei OR059 NC_011303 KM853177 KM853512 Acridoidea Acrididae Calliptaminae Calliptamus italicus OR193 NC_011305 KM853193 KM853497 Acridoidea Acrididae Catantopinae Coenona brevipedalis TAMUICIGC-003853 PP943135 PP932370 PP932378 Acridoidea Acrididae Catantopinae Serpusia opacula TAMUICIGC-003856 PP943136 PP932371 PP932379 Acridoidea Acrididae Catantopinae Xenocatantops brachycerus OR236 NC_021609 MG888296 MG888303 Acridoidea Acrididae Copiocerinae Copiocera sp. OR333 MG993384 KM853250 KM853440 Acridoidea Acrididae Coptacrinae Eucoptacra cauta OR509 MG993445 KM853324 KM853368 Acridoidea Acrididae CyrtacanthacridinaeCyrtacanthacris tatarica OR181 MG993444 KM853184 KM853506 Acridoidea Acrididae Euryphyminae Euryphymus sp. OR314 MG993388, MG993422, MG993436 KM853243 KM853447 Acridoidea Acrididae Eyprepocnemidinae Eyprepocnemis plorans OR309 MG993386, MG993418, MG993424, MG993425, MG993427, MG993433, MG993437, MG993450 KM853239 KM853451 Acridoidea Acrididae Gomphocerinae Prorocorypha snowi OR214 MG993438, MG993452, MG993453 KM853199 KM853491 Acridoidea Acrididae Hemiacridinae Leptacris kraussii OR304 MG993429 KM853238 KM853452 Acridoidea Acrididae Leptysminae Stenacris vitreipennis OR342 MN935544, MN935513, MN935578, MN935533, MN935523, MN935597, MN935555, MN935566, MN935609, MN935619, MN935630, MN935641 KM853255 KM853435 Acridoidea Acrididae Marelliinae Marellia remipes OR344 MG993387, MG993423, MG993442, MG993447 KM853256 KM853434 Acridoidea Acrididae Melanoplinae Melanoplus bivittatus OR245 MG993426 KM853211 KM853479 Acridoidea Acrididae Oedipodinae Locusta migratoria OR191 NC_001712 KM853191 KM853499 Acridoidea Acrididae Ommatolampidinae Ommatolampis quadrimaculata OR364 MG993443 KM853267 KM853423 Acridoidea Acrididae Oxyinae Oxya chinensis OR315 NC_010219 KM853244 KM853446 Acridoidea Acrididae Pauliniinae Paulinia acuminata OR345 MG993401, MG993416, MG993419, MG993430, MG993431, MG993446 KM853257 KM853433 Acridoidea Acrididae Proctolabinae Coscineuta sp. OR249 MG993441 KM853212 KM853478 Acridoidea Acrididae Rhytidochrotinae Paropaon sp. OR337 MG993393, MG993397, MG993421, MG993428, MG993449 KM853253 KM853437 Acridoidea Acrididae Spathosterninae Spathosternum nigrotaeniatum OR224 MG993439 KM853203 KM853487 Acridoidea Dericorythidae Dericorythinae Dericorys annulata NC_046555 NC_046555 N/A N/A Acridoidea Ixalidiidae n. fam. Ixalidium haematoscelis IXsp002 PP943126 PP932372 PP932394 Acridoidea Ixalidiidae n. fam. Ixalidium sjostedti Ixsj016 PP943125 PP932373 PP932395 Acridoidea Ixalidiidae n. fam. Mazaea cf granulosa TAMUICIGC-003854 PP943131 PP932366 PP932399 Acridoidea Ixalidiidae n. fam. Rowellacris n. gen. cf obscuripes TAMUICIGC-003734 PP943133 PP932369 PP932396 Acridoidea Ixalidiidae n. fam. Rowellacris n. gen. usambarica TAMUICIGC-003847 PP943134 PP932368 PP932397 Acridoidea Ixalidiidae n. fam. Tangana cf asymmetricaTan002 PP943137 PP932367 PP932398 Acridoidea Lentulidae Lentulinae Bacteracris sp. TAMUICIGC-002615 PP932356 PP932391 Acridoidea Lentulidae Lentulinae Lentula callani OR295 NC_020774 KM853234 KM853456 Acridoidea Lentulidae Lentulinae Usambilla sagonai TAMUICIGC-002676 PP932357 PP932393 Acridoidea Lentulidae Lentulinae Zulutettix tarranti TAMUICIGC-002670 PP932376 PP932392 Acridoidea Lentulidae Lithidiinae Lithidiopsis carinatus OR316 NC_020775 KM853245 KM853445 Acridoidea Ommexechidae Aucaridinae Aucacris bullocki OR580 PP943130 PP932351 PP932382 Acridoidea Ommexechidae Ommexechinae Graea horrida OR579 MN994068, MN994066, MN994062, MN994064, MN994060, MN994058, MN994056, MN994054, MN994050, MN994052 PP932352 PP932400 553 Ixalidiidae, new family of Acridoidea ZOOSYSTEMA • 2025 • 47 (24) Family Subfamily Genus Species Voucher Number mtDNA 18S 28S Acridoidea Ommexechidae Ommexechinae Ommexecha virens OR367 NC_020778 KM853269 KM853421 Acridoidea Ommexechidae Ommexechinae Spathalium audouini OR581 PP943132 PP932354 PP932380 Acridoidea Ommexechidae Ommexechinae Tetrixocephalus willemsei OR577 PP943129 PP932353 PP932381 Acridoidea Pamphagidae Porthetinae Hoplolopha asina OR288 PP932365 PP932402 Acridoidea Pamphagidae Prionotropisinae Prionotropis hystrix OR151 JX913764 KM853180 KM853509 Acridoidea Pamphagidae Thrinchinae Filchnerella beicki NC_024923 N/A N/A Acridoidea Pamphagidae Thrinchinae Haplotropis brunneriana NC_064211 N/A N/A Acridoidea Pamphagidae Thrinchinae Thrinchus schrenkii NC_014610 N/A N/A Acridoidea Pamphagogidae Hemicharilaus monomorphus OR540 JX913773 KM853337 KM853355 Acridoidea Pyrgacridae Pyrgacridinae Pyrgacris descampsi OR317 NC_020776 KM853246 KM853444 Acridoidea Romaleidae Romaleinae Xyleus modestus OR265 NC_014490 KM853221 KM853469 Acridoidea Romaleidae Romaleinae Chromacris trogon TAMUICIGC-004271 PP932355 PP932401 Acridoidea Romaleidae Romaleinae Romalea microptera OR1000 MG993392, MG993394, MG993454, MG993455, MG993456, MG993457 MG888294 MG888343 Acridoidea Tristiridae Atacamacridinae Atacamacris diminuta OR202 PP932350 PP932383 Acridoidea Tristiridae Tristirinae Bufonacris bruchi OR205 MN974272 PP932359 PP932384 Acridoidea Tristiridae Tristirinae Punacris peruviana OR206 PP932358 PP932390 Acridoidea Tristiridae Tristirinae Tristira magellanica OR204 NC_020773 KM853197 KM853493 Acridoidea Tristiridae Tristirinae Tropidostethus angusticollis OR203 MN994067, MN994065, MN994061, MN994063, MN994059, MN994057, MN994055, MN994053, MN994049, MN994048, MN994047, MN994051 PP932364 PP932388 Acridoidea Tristridae Tristirinae Circacris auris HS32 PP932361 PP932385 Acridoidea Tristridae Tristirinae Elasmoderus lutescens OR532 PP943127 PP932360 PP932386 Acridoidea Tristridae Tristirinae Eremopachys bergi HS34 PP932362 PP932387 Acridoidea Tristridae Tristirinae Peplacris recutita OR572 PP943128 PP932363 PP932389 Pneumoroidea Pneumoridae Bullacris membracioides TAMUICIGC-002428 PP932375 PP932404 Pneumoroidea Pneumoridae Physemacris variolosa OR293 NC_014491 KM853233 KM853457 Pyrgomorphoidea Pyrgomorphidae Orthacridinae Colemania sphenarioides OR286 MK531234-54 MK370970 MK370950 Pyrgomorphoidea Pyrgomorphidae Orthacridinae Ichthyotettix mexicanus OR1376 MK531214-33 MK370974 MK370954 Pyrgomorphoidea Pyrgomorphidae Orthacridinae Psedna nana OR528 MK514100 MK370982 MK370962 Pyrgomorphoidea Pyrgomorphidae Orthacridinae Sphenacris crassicornis OR1334 MK514099 MK370984 MK370964 Pyrgomorphoidea Pyrgomorphidae Pyrgomorphinae Tanita sp. OR283 MK514110 MK370987 MK370967 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Atractomorpha sinensis OR282 NC011824 PP932377 PP932403 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Chrotogonus hemipterus OR284 MK514108 MK370969 MK370949 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Monistria discrepans OR527 MK514105 MK370976 MK370956 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Phymateus morbillosus OR273 MK514103 MK370978 MK370958 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Poekilocerus buffonius OR152 MK514102 MK370980 MK370960 Pyrgomorphoidea Pyrgomorphoidea Pyrgomorphidae Sphenarium purpurascens OR1328 MK514107 MK370985 MK370966 Tanaoceroidea Tanaoceridae Tanaocerus koebelei OR559 NC_020777 KM853342 KM853350 Trigonopterygoidea Trigonopterygidae Trigonopteryginae Systella rafflesii MT011447, MT011493, MT011539, MT011587, MT011632, MT011721, MT011762, MT011807, MT011851, MT011897 N/A N/A Trigonopterygoidea Trigonopterygidae Trigonopteryginae Trigonopteryx hopei OR290 JX913767 KM853232 KM853458 Trigonopterygoidea Xyronotidae Xyronotus aztecus OR1175 MN935547, MN935516, MN935580, MN935536, MN935526, MN935600, MN935558, MN935569, MN935611, MN935622, MN935633, MN935644 PP932374 PP932405 Apprendix 1. — Continuation.