Orthochiroides vachoni Kovařík, 1998

Kovařík, František & Lowe, Graeme, 2022, Review of Orthochiroides Kovařík 1998 with description of a new species (Scorpiones: Buthidae), Euscorpius 349, pp. 1-42 : 14-20

Orthochiroides vachoni Kovařík, 1998

( Figures 54–81 , 84–86 , 103–110, 115–117, 119, 130–133, 140–141, 144–145, 205–211; Tables 1, 3)

Orthochiroides vachoni Kovařík, 1998: 117–120 , figs. 1–5, 16–20, tab. 1–2; Fet & Lowe, 2000: 193; Kovařík, 2002: 9; Kovařík, 2003: 135, 142, tab. 1; Kovařík, 2004: 24 .

Orthochirus vachoni: Lourenço & Ythier, 2021: 344 , figs. 16–20.

TYPE LOCALITY AND TYPE REPOSITORY. Somalia, Sar Uanle , about 20 km south from Chisimaio, 00°29'48"S 42°25'30"E ; MZUF.

TYPE MATERIAL EXAMINED. Somalia, Sar Uanle , about 20 km South from Chisimaio, 00°29'48"S 42°25'30"E, (for locality details see Messana et al., 1977, and Vanini et al., 1977), 18♂ (holotype and paratypes Nos. 1–17), 11♀ (paratypes Nos. 18–27), 9 juvs. (paratypes Nos. 28–36). Holotype (No. 533), allotypic paratype (No. 537), and paratypes Nos. 1–9, 20–29, 31–35 (No. 539) are in MZUF. Other paratypes are in BMNH, FKCP, MNHN, NMPC, SMFD, ZMHB, ZMUH (see Kovařík, 1998).

OTHER MATERIAL EXAMINED. Yemen. Socotra Island , XI.2000, 1♂, leg . V. Bejček & K. Šťastný , FKCP.

DIAGNOSIS (ADULT ♂ ♀). Total length of adults 24–35 mm. Petite ‘trichobothrium’ d 2 on dorsal surface of pedipalp femur absent; petite ‘trichobothrium’ d 2 on dorsal surface of pedipalp patella reduced or absent. Chela with carinae E and D1 strongly costate, intercarinal surfaces sparsely granulate or tuberculate. Pectinal tooth count: 17–20 (♂), 14–18 (♀). Movable finger of pedipalp chela with 8–9 rows of median denticles, 9 ID and 9 OD. Metasoma III–V laterally and ventromedially rugosereticulate and finely granulate. Inter-reticular depressions large, irregularly shaped, with diameters comparable to the mean distance between their centroids, together occupying much more area than the smooth or granular reticulations between them. Lateral median carinae present in male, weak, finely granulated, complete on metasoma I–II, restricted to posterior half of segment on metasoma III–IV. Dorsal surfaces of all metasomal segments weakly rugose. Metasoma IV–V with border between dorsal and dorsolateral surfaces clearly demarcated by dorsosubmedian carina, and in male by abrupt transition in morphosculpture. Aculeus moderately shorter than vesicle, aculeus L/telson L ~0.25. Color uniformly brown to black; femur, patella and chela manus of pedipalps brown; chela fingers, and tibia and tarsomeres of legs yellow to yellowish brown. Tergites roughly granulated. Sternite VII densely granulated, with four granulated carinae. Pedipalp, metasoma and telson glabrous. Moderate to small tibial spurs present on legs III and IV. Tarsomere I of legs I–III with 3–6 long setae in both sexes.

DISTRIBUTION. Somalia, Yemen ( Socotra Island) ( Fig. 119 ).

COMMENTS. The two widely disjunct records of O. vachoni : (i) an extensive type series including specimens of both sexes, and juveniles, from the type locality in southern Somalia ( Kovařík, 1998), and (ii) a single male specimen from Socotra Island ( Kovařík, 2004), are puzzling from a biogeographic perspective. Socotra Island is separated from the type locality by a distance of ca. 1,900 km, and isolated from the nearest mainland point on the coast of Africa by a 240 km wide marine barrier ( Fig. 119 ). Its fauna exhibits high endemism ( Cheung et al., 2006; Purchart et al., 2020). The other two species of Orthochiroides found on Socotra ( O. insularis and O. socotrensis ) are endemic, as are two other Socotra scorpions, Hemiscorpius socotranus Pocock, 1889 and Hottentotta socotrensis (Pocock, 1889) . This suggests that ‘ O. vachoni ’ from Socotra might also be an endemic species different from O. vachoni on the mainland. However, the Socotra specimen is virtually identical to all paratype males of O. vachoni that we have examined ( Figs. 58–81 , Tab. 1). There are only a few minor differences that lie well within the scope of intraspecific variation typical for other buthids (i.e., sternite VII fine granulation slightly more intense; metasoma III-IV median lateral carinae slightly less visible and partially obscured in both by strong reticulate morphosculpture; small morphometric differences in metasoma V). In our opinion, these differences are insufficient for the diagnosis of a new species. The other mainland African species O. somalilandus sp. n. differs more from O. vachoni , than does the specimen from Socotra. The collection of an extensive type series of O. vachoni from southern Somalia ( Kovařík, 1998), and the presence of a closely similar species in Somaliland, indicate that this species occurs naturally on the mainland. We cannot exclude the possibility that the Socotra record is spurious and possibly an introduction by human transport. Other non-endemic flora and fauna occur on or have been introduced to the island (e.g., Hůla & Niedobová, 2020; Senan et al., 2010; Witt et al., 2020). The range of distribution of O. vachoni in Somalia is unknown. It may not be confined to its type locality, and could extend further up the coast closer to Socotra. Without further information, we take a conservative approach and provisionally classify the Socotra record as O. vachoni .

In their paper synonymizing Orthochiroides with Orthochirus, Lourenço & Ythier (2021) examined a single male paratype of Orthochiroides vachoni deposited in MNHN, and illustrated its metasomal segment V and telson in lateral view (Lourenço & Ythier, 2021: 344, fig. 20). They depicted the morphosculpture on the lateral surface of metasoma V as consisting of numerous small, rounded depressions or punctae of uniform size and shape, with diameters much less than the mean distance between their centroids, that together occupy much less area than the smooth surfaces between them. This is similar to the punctate morphosculpture on metasoma V of most species of Orthochirus . Their illustration differs from the illustration of a rugose-reticulate morphosculpture on the lateral surface of the male holotype published in the original description of O. vachoni ( Kovařík, 1998: 117, fig. 1). In that figure, the depressions are depicted as more irregular in size and shape, including larger diameters comparable to the mean distance between their centroids, together occupying as much or more area than the surface between them. Kovařík (1998: 117–119, figs. 4–6) described the larger depressions on the metasoma of O. vachoni and emphasized their difference from the punctae of Orthochirus . This morphosculpture is documented again here photographically for comparison to fig. 20 of Lourenço & Ythier (2021) (cf. Figs. 60–63 , 84–86 ). Kovařík (1998) analyzed the entire type series of O. vachoni consisting of 38 specimens, including the paratype deposited in MNHN, and did not report any examples of fine punctate morphosculpture on the metasoma. We regard fig. 20 of Lourenço & Ythier (2021) to be a gross misrepresentation of the true anatomy of O. vachoni .

Figures 87–118: Comparation of Orthochiroides spp. , pedipalp chela dorsal and external (87–88, 91–92, 9–96, 99–100, 103–104, 107–108), patella dorsal and external (89–90, 93–94, 97–98, 101–102, 105–106, 109–110), and movable finger dentation (111–118). Figures 87–94, 111–112. Orthochiroides insularis , Socotra Island, male (87–90, 111) and female (91–94, 112). Figures 95–102, 113–114. O. socotrensis , male holotype (95–98, 113) and female paratype (99–102, 114). Figures 103–110, 115–117. O. vachoni , male paratype No. 11 (103–106, 115), female paratype No. 18 (107–110, 116) and male from Socotra (117). Figure 118. O. somalilandus sp. n., female pratype.

Figures

Figure 119. Geographic distribution of Orthochiroides spp.

Figures 54–57: Orthochiroides vachoni, paratypes, FKCP. Figures 54–55. Male, dorsal (78) and ventral (79) views. Figures 56–57. Female, dorsal (80) and ventral (81) views. Scale bar: 10 mm.

Figures 58–59. Orthochiroides vachoni, male from Socotra, dorsal (58) and ventral (59) views.

Figures 60–63. Orthochiroides vachoni, male from Socotra, metasoma V and telson lateral (60), and metasoma and telson, lateral (61), dorsal (62), and ventral (63) views. Scale bar: 10 mm (61–63).

Figures 64–81: Orthochiroides vachoni, male from Socotra. Figures 64–75. Pedipalp. Chela, dorsal (64), external (65), and ventral (66) views. Patella, dorsal (67), external (68) and ventral (69) views. Femur and trochanter, internal (70), dorsal (71), ventral (72), and external (73) views. Movable (74) and fixed (75) finger dentation. Trichobothrial pattern indicated in Figures 64–68, 70–71 by white circles. Figures 76–77. Carapace and tergites I–VI (76), sternopectinal region and sternites (77). Figures 78–81. Right legs I–IV, retrolateral aspect.

Figures 82–86: Orthochiroides, males. Figures 82. O. insularis, metasoma and telson, ventral view. Figures 82. O. socotrensis, holotype, metasoma and telson ventral view. Figures 84–86. O. vachoni, paratype, metasoma and telson, lateral (84), ventral (85), and dorsal (86) views. Scale bars: 10 mm (82–83, 84–86).