Leiurus Ehrenberg, 1828

Kovařík, František & Lowe, Graeme, 2020, Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part XXIV. Leiurus (Buthidae), with description of Leiurus gubanensis sp. n., Euscorpius 309, pp. 1-19 : 1

Genus Leiurus Ehrenberg, 1828

( Figures 1–91 , Table 1 )

Androctonus (Leiurus) Ehrenberg in Hemprich & Ehrenberg, 1828, pl. I, fig. 5; Hemprich & Ehrenberg, 1829: 353 (in part).

Leiurus: Vachon, 1949: 83–88 (1952: 203–208); Fet & Lowe, 2000: 155–157; Lowe et al., 2014: 1–129 , figs. 1–100 (complete reference list).

TYPE SPECIES. Androctonus (Leiurus) quinquestriatus Ehrenberg, 1828 .

DIAGNOSIS. Medium to large sized buthid scorpions, total length 50–115 mm. The carapace is almost flat, weakly or moderately trapezoidal, with anterior margin straight or slightly concave, and 5 lateral eyes in ‘ type 5’ pattern ( Loria & Prendini, 2014). Both carapace and tergites bear granulated carinae. The carapace bears distinct anterior, superciliary, central median, central lateral, posterior median and posterior lateral carinae. The central lateral and posterior median carinae are fused into a lyre configuration. Tergites I–II, VII bear 5 carinae, and III– VI bear 3 carinae. Tergites lack macrosetae. The metasoma is elongate, metasoma I–III bear 10 carinae, with median lateral carinae complete on I, and reduced on II–III. Metasoma IV bears 8 carinae, and metasoma V bears 7 carinae of which the dorsolateral carinae are weak, and ventrolateral carinae are strong with serrate or lobate dentition. The telson has a relatively bulbous vesicle lacking a subaculear spine or tubercle. Pectines bear fulcra. Pectinal tooth count ranges are ♂ 28–43, ♀ 25–38. The hemispermatophore is flagelliform, the capsule having 3 sperm hemiduct lobes well separated from the flagellum, and a strong hook-like basal lobe. The chelicerae exhibit characteristic buthid dentition ( Vachon, 1963), with two denticles on the ventral aspect of the fixed finger. The pedipalp chela is slender with long fingers, the surface smooth with carinae reduced or obsolete, and the dentate margins of the fingers are armed with linear, non-imbricated subrows of primary denticles, flanked by internal and external accessory denticles. The movable finger bears two enlarged subdistal internal denticles. The pedipalps are orthobothriotaxic, pattern type Ab ( Vachon 1974, 1975), the femur with trichobothrium d 2 on its dorsal surface, and the patella with d 3 internal to the dorsomedian carina. The chela manus has Eb 1 - Eb 2 angled proximally, and Eb 1 - Eb 2 - Eb 3 acute angle opening in the distal direction (δ -configuration). Tibial spurs are present on legs III–IV, and basitarsi I–III bear regular series of macrosetae on retrosuperior, retroinferior and inferior margins. On the ventral surfaces of telotarsi are paired rows of macrosetae, and prolateral and retrolateral tarsal spurs are present on all legs. Sexual dimorphism: compared to females, males have a narrower mesosoma, more robust carination on tergites and sternites III–V, more slender pedipalps and metasoma, longer pectines with larger teeth, and weaker dentition or granulation on ventromedian carinae of metasoma II–III. Males are similar to females in lacking undulate dentate margins at the base of the pedipalp fingers.

Figures

Figures 1–4: Leiurus gubanensis sp. n., 18SF.Figures 1–2. Male holotype in dorsal (1) andventral (2) views.Figures 3–4. Female paratopotype in dorsal (3) and ventral (4) views. Scale bar: 10 mm.

Figures 5–10: Leiurus gubanensis sp. n., male subadult paratype, 11SG. Figures 5–6. Dorsal (5) and ventral (6) views. Figures 7–10. Telson and metasoma V lateral (7), and metasoma and telson lateral (8), dorsal (9), and ventral (10) views. Scale bars: 10 mm (5–6, 8–10).

Figures 11–20: Leiurus gubanensis sp. n., 18SF. Figures 12–13, 15–17. Male holotype, metasoma V and telson ventral (12) and lateral (13), and metasoma and telson lateral (15), dorsal (16), and ventral (17) views. Figures 11, 14, 18–20. Female paratopotype, metasoma V and telson ventral (11) and lateral (14), and metasoma and telson lateral (18), dorsal (19), and ventral (20) views. Scale bars: 10 mm (15–17, 18–20).

Figures 21–32: Leiurus gubanensis sp. n., 18SF. Figures 21, 23, 25–28. Male holotype, carapace and tergites I–III (21), coxosternal area and sternites (23), left legs I–IV, retrolateral aspect (25–28 respectively). Figures 22, 24, 29–32. Female paratopotype, carapace and tergites I–III (22), coxosternal area and sternites (24), left legs I–IV, retrolateral aspect (29–32 respectively).

Figures 33–56: Leiurus gubanensis sp. n., 11SG. Figures 33–45, 54. Male subadult paratype, carapace and tergites I–IV (33), coxosternal area and sternites (34), left legs I–IV, retrolateral aspect (35–38 respectively), chela dorsal (39), external (40) and ventral (41) views, patella dorsal (42), external (43) and ventral (44) views, trochanter and femur dorsal (45), and movable finger dentition (54). Figures 46–53, 55–56. Female adult paratype, chela dorsal (46), external (47) and ventral (48) views, patella dorsal (49), external (50) and ventral (51) views, trochanter and femur dorsal (52) and ventral (53) views, and movable (55) and fixed (56) finger dentition.

Figures 57–69: Leiurus gubanensis sp. n., 18SF. Figures 57–58. Female paratopotype, chela dorsal (57) and external (58) views. Figures 59– 69. Male holotype, chela dorsal (59), external (60) and ventral (61) views, patella dorsal (62), external (63) and ventral (64) views, trochanter and femur internal (65), dorsaloexternal (66) and ventral (67) views, and right chelicera in dorsal (68) and ventral (69) views. Trichobothrial pattern is indicated by white circles (59–63, 65–66).

Figures 70–79: Leiurus gubanensis sp. n., comparison of key characters of male subadult paratype from 11SG (70, 72, 74, 76, 78) and female paratopotype from 18SF (71, 73, 75, 77, 79). Figures 70–73. Tergites I–III under white light (70–71) and UV fluorescence (72–73). Figures 74– 75. Sternite III under UV fluorescence.Figures 76–79. Metasoma V and telson ventral under UV fluorescence (76–77) and white light (78–79).

Figures 80–81: Leiurus gubanensis sp. n., 18SF, male holotype, carapace and tergites (80) and coxosternal area and sternites (81) under UV fluorescence.

Figures 82–83: Leiurus gubanensis sp. n., 18SF, female paratopotype, carapace and tergites (82) and coxosternal area and sternites (83) under UV fluorescence.

Figures 84–85: Leiurus gubanensis sp. n., 18SF, male holotype (84) and female paratopotype (85) in vivo habitus.

Figures 86–87: Leiurus gubanensis sp. n., 11SG, male subadult paratype (86) in vivo habitus and its locality (87).

Figures 88–89: Figure 88. Distribution of Leiurus gubanensis sp. n., L. quinquestriatus and L. somalicus in the region. Figure 89. Type locality (18SF) of L. gubanensis sp. n.

Figures 90–91: Scaling of relative size of median ocular tubercle with relative size of median eyes in the genus Leiurus. Ordinates of scatter plots are the ratio median ocular tubercle width/ carapace L, and abscissas are the ratio median eye diameter/ carapace L, in males (90) and females (91). Plotted symbols represent measurements from a single sample of each species, extracted or estimated from published images and data, or from our own material. Lines are least squares regression fits, and the corresponding correlation coeeficients R, and P-values are indicated. In both sexes, L. gubanensis sp. n. is well separated from other species in having the largest eyes in the genus.