A redescription of Leiurus libycus (Birula, 1908), stat. n. (Scorpiones: Buthidae)

A redescription of Leiurus libycus (Birula, 1908), stat. n. (Scorpiones: Buthidae) Ersen Aydın Yağmur, František Kovařík & Victor Fet April 2025 — No. 413 Euscorpius Occasional Publications in Scorpiology EDITOR: Victor Fet, Marshall University, ‘[email protected]’ ASSOCIATE EDITOR: Michael E. Soleglad, ‘[email protected]’ TECHNICAL EDITOR: František Kovařík, ‘[email protected]’ Euscorpius is the first research publication completely devoted to scorpions (Arachnida: Scorpiones). Euscorpius takes advantage of the rapidly evolving medium of quick online publication, at the same time maintaining high research standards for the burgeoning field of scorpion science (scorpiology). Euscorpius is an expedient and viable medium for the publication of serious papers in scorpiology, including (but not limited to): systematics, evolution, ecology, biogeography, and general biology of scorpions. Review papers, descriptions of new taxa, faunistic surveys, lists of museum collections, and book reviews are welcome. Derivatio Nominis The name Euscorpius Thorell, 1876 refers to the most common genus of scorpions in the Mediterranean region and southern Europe (family Euscorpiidae). Euscorpius is located at: https://mds.marshall.edu/euscorpius/ Archive of issues 1-270 see also at: http://www.science.marshall.edu/fet/Euscorpius (Marshall University, Huntington, West Virginia 25755-2510, USA) ICZN COMPLIANCE OF ELECTRONIC PUBLICATIONS: Electronic (“e-only”) publications are fully compliant with ICZN (International Code of Zoological Nomenclature) (i.e. for the purposes of new names and new nomenclatural acts) when properly archived and registered. All Euscorpius issues starting from No. 156 (2013) are archived in two electronic archives: • Biotaxa, http://biotaxa.org/Euscorpius (ICZN-approved and ZooBank-enabled) • Marshall Digital Scholar, http://mds.marshall.edu/euscorpius/. 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For further details on the new ICZN amendment, see http://www.pensoft.net/journals/zookeys/article/3944/. Publication date: 23 April 2025 http://zoobank.org/urn:lsid:zoobank.org:pub:773ECC36-4301-44B4-B246-E0CEC270FFFD Euscorpius - Occasional Publications in Scorpiology. 2025, No. 413 Introduction A number of species of the genus Leiurus have been described from Africa. Traditionally, known populations of Leiurus in Africa were identified as L. quinquestriatus (Ehrenberg, 1828). However, studies over the past two decades have revealed that some of these populations represent new species. The status Buthus quinquestriatus libycus Birula, 1908 so far remained unclear. It was described as a subspecies from the “Libyan Desert”, based on a subadult male specimen (Birula, 1908). This taxon was later synonymized with Leiurus quinquestriatus (Ehrenberg, 1828) by Vachon (1949), without examination of the holotype. Subsequent studies have not recognized Birula’s taxon as valid. Currently, the following 12 species are known in northern and sub-Saharan Africa: L. aegyptiacus Lourenço & El-Hennawy, 2021; L. ater Lourenço, 2019; L. dekeyseri Lourenço, 2020; L. gubanensis Kovařík & Lowe, 2020; L. hoggarensis Lourenço, Kourim & Sadine, 2018; L. nigerianus Lourenço, 2021; L. quinquestriatus (Ehrenberg, 1828); L. saharicus Lourenço, 2020; L. savanicola Lourenço, Qi & Cloudsley-Thompson, 2006; L. somalicus Lourenço & Rossi, 2016; and L. tamajeq Lourenço & Ythier, 2024 (Rein, 2025). The nominotypic species of the genus, Leiurus quinquestriatus, was recently redescribed by Lowe et al. (2014) in a detailed revision of the genus; however, position of “Buthus quinquestriatus libycus” has not been evaluated. In this study, B. quinquestriatus libycus is reviewed and recognized as a valid taxon. Its classification under the genus Leiurus is confirmed, and it is elevated to species level as Leiurus libycus (Birula, 1908), stat. n. In addition, since the type locality of this species is western Egypt (between Alexandria and Fayum), we synonymize here L. aegyptiacus Lourenço & El-Hennawy, 2021 = L. libycus, stat. n., syn. n. Material and methods The focus stacking method was modified by Brecko et al. (2014). The trichobothrial nomenclature after Vachon (1974, 1975) and morphological nomenclature after Francke (1977), Stahnke (1971), and Hjelle (1990). The examined holotype specimen of L. libycus, stat. n., is deposited at Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia (ZISP, 567 (45)). Systematics Buthidae C. L. Koch, 1837 Leiurus Ehrenberg, 1828 Leiurus libycus (Birula, 1908), stat. n. (Figures 1–3, 5–19) http://zoobank.org/urn:lsid:zoobank.org:act:0F81B8FAD04C-4A9C-9C4A-35FD82147455 Buthus quinquestriatus libycus Birula, 1908: 129. Buthus quinquestriatus libycus: Birula, 1910: 118; Vachon, 1949: 90. = Leiurus aegyptiacus Lourenço & El-Hennawy, 2021: 326333, fig. 1–14, 16, fig. 15, 18 (map). Syn. n. Type locality and type depository. Egypt (see below), Libyan Desert, ZISP 567 (45). A redescription of Leiurus libycus (Birula, 1908), stat. n. (Scorpiones: Buthidae) Ersen Aydın Yağmur1*, František Kovařík2, & Victor Fet3 1 Manisa Celal Bayar University, Alaşehir Vocational School, Alaşehir, Manisa, 45600 Turkey. email: [email protected] 2 Department of Zoology, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic; www.scorpio.cz 3 Department of Biological Sciences, Marshall University, Huntington, West Virginia 25755–2510, USA; email: [email protected] * Corresponding Author http://zoobank.org/urn:lsid:zoobank.org:pub:773ECC36-4301-44B4-B246-E0CEC270FFFD Summary Buthus quinquestriatus libycus was described by Birula (1908) from the Libyan Desert, based on a subadult male specimen. This taxon was later synonymized with Leiurus quinquestriatus (Ehrenberg, 1828) by Vachon (1949). In this study, we re-evaluate this taxon and recognize it as Leiurus libycus (Birula, 1908), stat. n., providing a redescription based on the holotype. The type locality of this species is clarified as western Egypt (between Alexandria and Fayum). We synonymize Leiurus aegyptiacus Lourenço & El-Hennawy, 2021 with L. libycus, stat. n., syn. n. 2Euscorpius - 2025, No. 413 Figures 1–7. Leiurus libycus (Birula, 1908), stat. n., holotype, dorsal (1) and ventral (2) views, telson lateral (3), the original label handwriting of A. A. Birula (4), metasoma and telson in lateral (5), dorsal (6), and ventral (7) views. Scale bars = 10 mm (1–2, 5–7). Yağmur, Kovařík & Fet: A redescription of Leiurus libycus (Birula, 1908), stat. n. 3 Type material. Holotype, juv. ♂, [Egypt] Libyan Desert, 1879, leg. Dr. [Wilhelm] Junker. Diagnosis. The base color is pale dark yellow. Carapace subtrapezoidal; Median eyes located slightly anterior to the middle of the carapace. Five couple lateral eyes (3 large, 2 small) present on each side. Central lateral and posterior median carinae fused forming a lyre-shaped figure. Posterior median and posterior lateral carinae terminate with inconspicuous spinoid protrusions. Anterior median carinae do not extend to the anterior margin, and the area between them with two groups of rounded granules. The rest intercarinal area smooth but some scattered medium granules present between posterior median carinae and posterior lateral carinae. Tergites I–II bear 5 granular carinae, terminate with inconspicuous spinoid protrusions. Tergites III–VI bear 3 moderate and moderately granulated carinae, terminate with inconspicuous spinoid protrusions that extending slightly beyond the posterior margins. The pectinal tooth count is 35–43. Pedipalps orthobothriotaxic, pattern type A β (Vachon 1974, 1975), the femur with trichobothrium d2 on its dorsal surface. The femur bears five and patella bears seven carinae. Chela slender and elongated. Manus relatively short and rounded whereas fingers elongated (Movable finger length/manus length ratio= 3.08, chela length/manus width ratio= 6.45). The pedipalp movable and fixed fingers bear 12 principal rows of denticles, with external and internal accessory granules and four distal granules. Fixed fingers bear 12 principal rows of denticles, with external and internal accessory granules, only last row of denticles without external accessory granules. Trichobothrium et is located between dt and db, and proximal to dt; trichobothrium db located between et and est, so proximal to est, almost opposite. Metasomal segments moderately slender; I L/W 1.42; II L/W 1.96; III L/W 2.18; IV L/W 2.67; V L/W 3.04. Metasomal segments I-III bear 10, IV bears 8 and V bears 5 carinae. Ventrolateral carinae of segment V strong with dentate granules increasing in size posteriorly, with several somewhat large subconical and pointed denticles. Vesicle smooth, bulbous and sparsely setose. Aculeus abruptly curved and slightly shorter than the vesicle. Redescription (based on subadult male holotype). Coloration (Figs. 1–2). The base color is pale dark yellow. The chelicerae are pale yellow without reticulation. The ventral submedian and ventrolateral carinae of metasoma II– IV lack pigmentation, and metasoma V yellowish brown but most posterior portion of segment dark yellow. Vesicle and base of aculeus dark yellowish, tip of aculeus reddish. Carapace and mesosoma (Figs. 1–2, 17–18). Carapace subtrapezoidal; lateral margins of carapace parallel at posterior quarter, whereas steeply sloped at anterior ¾ and there is first a depression and then a convexity here. The anterior margin of the carapace is almost straight and crenulate, with bordered by a row of moderate granules. Median eyes located slightly anterior to the middle of the carapace. Five couple of lateral eyes (3 large, 2 small) present on each side. The carinae are typical for the genus Leiurus, with moderate and granular anterior median, superciliary, central lateral, central median, posterior median and posterior lateral carinae. Central lateral and posterior median carinae fused forming a lyre-shaped figure. Posterior median and posterior lateral carinae terminate with inconspicuous spinoid protrusions. Anterior median carinae do not extend to the anterior margin, and the area between them with two groups of rounded granules. The rest intercarinal area smooth but some scattered medium granules present between posterior median carinae and posterior lateral carinae. The area between the posterior median carinae is depressed area with a shallow median furrow forming inverted “T”. Tergites I–II bear 5 granular carinae, terminate with inconspicuous spinoid protrusions; median carinae indistinct, granules fine to medium; submedian carinae indistinct, granules fine to medium, aligned with the posterior median carinae of the carapace; lateral carinae moderate and oblique, granules moderate to coarse, aligned with the posterior lateral carinae of the carapace. Tergites III–VI bear 3 moderate and moderately granulated carinae, terminate with inconspicuous spinoid protrusions that extending slightly beyond the posterior margins. The surface between submedian carinae finely granular, lateral flanks sparsely granular with coarse granules in tergites I–VI. Tergite VII is pentacarinate, with all carinae strong and moderately granular, and submedian and lateral carinae are joined anteriorly by transverse granule rows. Intercarinal area smooth with scattered coarse granules. Sternite III–IV shagreened but poststernites smooth medially; bear weak and finely granular four carinae. Sternite VII shagreened with moderate and moderately granular four carinae. The pectinal tooth count is 35–43. The pectinal marginal tips extend to half of the length of sternite V and almost reach trochanter-femur joint. The pectines have three marginal lamellae and 7–8 middle lamellae. The lamellae bear numerous stout macrosetae. Pedipalps (Figs. 8–16). Pedipalps orthobothriotaxic, pattern type A and in β (Vachon 1974, 1975), the femur with trichobothrium d2 on its dorsal surface. The femur bears five carinae. Dorsointernal, dorsoexternal and ventrointernal carinae strong with coarse, closely spaced rounded granules. Internal carina strong and crenulate, with irregular large and spaced conical granules. External median carina moderate with irregular subspinoid granules. Dorsal surface sparsely granular, ventral surface smooth. Patella bears seven coarsely granular carinae. Dorsointernal carina is strong and crenulate with somewhat large 7-8 subconical granules and distinct dorsal patellar spur. Dorsomedian carina moderate with fine granulation. Dorsoexternal and ventromedian carina weak, almost smooth, bears a few minute granules. External median and ventral external carinae weak and smooth. Ventrointernal carina is strong and crenulate, with well-spaced mediumsized granules and without ventral patellar spur. Chela slender and elongated. Manus relatively short and rounded whereas fingers elongated (Movable finger length/manus length ratio= 3.08, chela length/manus width ratio= 6.45). The Euscorpius - 2025, No. 413 4 Figures 8–18: Leiurus libycus (Birula, 1908), stat. n., holotype. Figures 8–16. Pedipalp chela dorsal (8), external (9) and ventral (10) views, patella dorsal (11), external (12) and ventral (13) views, movable finger (14), femur and trochanter dorsal (15) and ventral (16) views. The trichobothrial pattern (dt, db, et, est) is indicated by green dots. Figures 17–18. Carapace and tergites I–IV (17) and sternopectinal region with sternites III–VII (18). Yağmur, Kovařík & Fet: A redescription of Leiurus libycus (Birula, 1908), stat. n. 5 Figure 19. Distal segments of legs II–IV, retrolateral view. Euscorpius - 2025, No. 413 6 pedipalp movable and fixed fingers bear 12 principal rows of denticles, with external and internal accessory granules and four distal granules. Fixed fingers bear 12 principal rows of denticles, with external and internal accessory granules, only last row of denticles without external accessory granules. Trichobothrium et located between dt and db, and proximal to dt; trichobothrium db located between et and est, so proximal to est, almost opposite. Legs (Fig. 19). Leg pairs III and IV bear long tibial spurs. Leg pairs I-IV with tarsal spurs. The telotarsi of legs bear two rows of spiniform macrosetae on their ventral surfaces. Basitarsi I– III bear bristle-combs, and basitarsus III has 16 retrosuperior macrosetae. Metasoma and telson (Figs. 3, 5–7). Metasomal segments moderately slender; I L/W 1.42; II L/W 1.96; III L/W 2.18; IV L/W 2.67; V L/W 3.04. Metasomal segments I-III bear 10, IV bears 8 and V bears 5 carinae. Lateral inframedian carinae complete and granular on segment I; incomplete, reduced on segment I-II, presents anterior 1/3 and bears 8 granules on segment II and presents anterior 1/4 and bears 5 granules on segment III. Dorsolateral carinae strong, finely serrate on segments I-II with fine subspinoid granules, almost smooth on segments III-IV. Lateral supramedian and ventrolateral carinae moderate and faintly serrate on segments I–IV, granules small and almost fixed. Ventral submedian carinae moderate on segments I–IV, serratocrenulate on segment I with small granules, serratocranulate to serrate on segments II and III with small granules, crenulate on segment IV. Segment V: Dorsolateral carinae moderate, rounded and sparsely granular. Ventrolateral carinae strong with dentate granules increasing in size posteriorly, with several somewhat large subconical and pointed denticles. Ventromedian carina moderate, armed with small to large dentate and spaced granules. Segments I-V sparsely setose. Intercarinal surfaces smooth on segment I-V, only lateral surfaces with some scattered minute granules. Telson: Vesicle smooth, bulbous and sparsely setose. Aculeus abruptly curved and slightly shorter than the vesicle. Affinities. Birula (1908) compared the subspecies he described with two others, now recognized as L. hebraeus (Birula, 1908) and L. quinquestriatus (Ehrenberg, 1828). According to Birula (1908), the pectinal tooth count in males of L. libycus, stat. n. was 35–43, whereas it was 33–35 in L. hebraeus and 32–36 in L. quinquestriatus. Lowe et al. (2014) reported the pectinal tooth count as 30–39 in L. hebraeus and 33–37 in L. quinquestriatus for males. This character is valid, but more specimens should be examined to determine the exact range of pectinal tooth counts. Birula (1908) reported the number of granules on the ventral carinae of metasomal segment III as 27–30 in Leiurus libycus, stat. n., 15–17 in L. hebraeus, and 20–23 in L. quinquestriatus in males; for metasomal segment V, the Figure 20. A page from the handwritten catalog of A.A.Birula, preserved in ZISP. Yağmur, Kovařík & Fet: A redescription of Leiurus libycus (Birula, 1908), stat. n. 7 granule count was 35–43 in L. libycus, stat. n., 24–31 in L. hebraeus, and 25–38 in L. quinquestriatus in males. These characters are variable, and therefore, a series of specimens of L. libycus, stat. n., L. hebraeus, and L. quinquestriatus should be examined in detail with regard to this character. Consequently, we do not confirm this character here as diagnistic. L. aegyptiacus Lourenço & El-Hennawy, 2021; L. ater Lourenço, 2019; L. hoggarensis Lourenço, Kourim & Sadine, 2018; L. quinquestriatus (Ehrenberg, 1828); and L. tamajeq Lourenço & Ythier, 2024 are known from regions surrounding the distribution of L. libycus, stat. n. Therefore, we compared L. libycus, stat. n. with these species. L. aegyptiacus was described based on a subadult female by Lourenço & El-Hennawy (2021). The vesicle of this specimen is elongated; however, females of L. libycus, stat. n. are unknown. The trichobothria db and est are positioned at approximately the same level on the fixed finger in L. aegyptiacus, L. tamajeq, and L. libycus, stat. n., whereas in L. hoggarensis and L. quinquestriatus, the trichobothrium db is located roughly in the middle between et and est. The trichobothrium et is proximal to est in L. tamajeq, whereas it is proximal to dt in L. aegyptiacus and L. libycus, stat. n. In L. ater, the trichobothrium db is located between dt and et, which is atypical for all known Leiurus species. The ventrolateral carinae bear several somewhat large, subconical, and pointed denticles in L. libycus, stat. n., whereas they bear smaller, subtriangular or subspinoid denticles in L. quinquestriatus. Comments. L. libycus, stat. n., was originally described as a subspecies of L. quinquestriatus, but it clearly differs from this species. The holotype of L. libycus, stat. n. was collected by Wilhelm Junker (1840-1892), a famous Russian traveller and ethnographer who travelled mainly to sub-Saharan Africa. Junker’s first travel to Africa in 1875 included initial training trip to the ‘Libyan Desert’ within the borders of modern Egypt (between Alexandia and Fayum); he returned there again in 1879 (Petri, 1891). The type locality of L. aegyptiacus (northeast of Maghra, east of the Qattara Depression, about 52 km southeast of El Alamein; 30°23’3.84”N, 29°10’0.12”E) is also situated within this area. Furthermore, the trichobothrial pattern on the fixed finger of the pedipalp is nearly identical in both species. Therefore, we synonymize Leiurus aegyptiacus Lourenço & El-Hennawy, 2021 with L. libycus, stat. n., syn. n. Acknowledgements We thank Viktor A. Krivokhatsky (1954–2021), Alexander Koval, Julia V. Samartseva, Sergey Yu. Sinev, and other employees of the Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia (ZISP) for their hospitality and help to F. K. and E. A. Y. in 2018–2019 while studying and imaging the wonderful Birula’s scorpion collection in St. Petersburg. References BIRULA, A. A. 1908. Ergebnisse der mit Subvention aus der Erbschaft Treitl unternommenen zoologischen Forschungsreise Dr. F. Werner’s nach dem ägyptischen Sudan und Nord-Uganda. XIV. 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