Buthacus occidentalis Vachon, 1953

Kovařík, František, Lowe, Graeme & Šťáhlavský, František, 2016, Review of Northwestern African Buthacus, with description of Buthacus stockmanni sp. n. from Morocco and Western Sahara (Scorpiones, Buthidae), Euscorpius 236, pp. 1-18 : 2-4

Buthacus occidentalis Vachon, 1953

( Figs. 46–48, 52–55, 63)

Buthacus leptochelys occidentalis Vachon, 1953: 1017– 1020 , figs. 3–9; Fet & Lowe, 2000: 84–85 (complete reference list until 2000).

Buthacus occidentalis: Lourenço, 2000: 5 ; Lourenço, 2001: 259; Lourenço, 2004: 230; Lourenço, 2006: 62, figs 10–12; Lourenço, 2013: 97, figs. 10–11.

= Buthacus ehrenbergi Kovařík, 2005: 3–5 , figs. 3–4, table 1 (syn. by Lourenço, 2006: 62).

= Buthacus huberi Lourenço, 2001: 257–259 , figs. 1, 4– 9, 23. Syn. n.

TYPE LOCALITY AND TYPE DEPOSITORY. Mauritania, Chinguetti , designated according to lectotype by Lourenço (2006), MNHN-RS-1676 .

TYPE MATERIAL EXAMINED. Mauritania, Chinguetti env., 20°26’N - 12°26’W, 1♂ ( Figs. 46–48, 52–55, holotype of Buthacus ehrenbergi Kovařík, 2005 ), leg . R. Demis , FKCP; south of Aftout , 2.VIII.1994, 1♂ juv. (holotype of Buthacus huberi Lourenço, 2001 , incorrectly cited in

original description as adult female), ZMUH No. A23 /01.

DIAGNOSIS. Total length 44–50 mm; carapace densely granulated with only anterior median carinae developed; anterior margin of carapace straight; pectine teeth 23–29 in male and 19–23 in female; sternites III––VI lacking carinae; sternite VII with four smooth carinae; metasomal segments I–IV with intercarinal surfaces smooth or almost smooth; metasomal segment V of both sexes ventrally granulated; metasomal segment I bears 10 carinae, segments II–IV bear 8 carinae (lateromedial carinae on segments II–III indicated by several granules on posterior part only); ventrolateral carinae of metasomal segment V bear several lobate granules in their posterior half; dorsal and lateral surfaces of segment V smooth, without granules in both sexes; all metasomal segments sparsely setose; metasomal segment V with ca. 35 long setae in both sexes; telson with long curved aculeus, longer than vesicle in both sexes; legs I–III with tarsal bristle combs composed of long, thin setae; tibial spurs present on legs III–IV, moderate on leg IV and extremely reduced or absent on leg III; movable and fixed fingers of pedipalp with 9 rows of granules, with external and internal accessory granules ( Buthacus leptochelys complex). Males with broader pedipalp chelae than females, fingers straight in both sexes.

COMMENTS. Lourenço (2001: 257) stated that the types of Buthacus huberi are two females (the male is unknown) that have 28 pectinal teeth, from which he conjectured that in "males it should range from 30–33" and so created a fictive incorrect character for distinguishing between B. huberi and B. occidentalis . He acknowledged that Vachon (1953) cited for B. occidentalis 26–29 pectinal teeth in males and 20–25 in females, but explained (Lourenço, 2001: 268, Lourenço, 2004: 230) that "the most common for B. occidentalis are 23 or 24 to (sic) males and 21 for females" and the high number of pectinal teeth cited by Vachon (1953) is due to the fact that Vachon "referred to specimens from Morocco (now lost)". The type series of B. occidentalis included specimens from Mauritania and southern Morocco, and Lourenço (2006: 62) designated as lectotype a specimen from the locality of Chinguetti in Mauritania, which ‘coincidentally’ happens to be the type locality of B. ehrenbergi Kovařík, 2005 , thereby synonymizing the latter species. The lost Morocco syntypes were presumed to be the same species (c.f. fig. 23 in Lourenço, 2001: 267). In fact, the Morocco populations represent a different undescribed species, which we here describe as B. stockmanni sp. n.. However, by designating as a lectotype of B. occidentalis a male from Mauritania with 27–28 pectinal teeth, Lourenço contradicted his own previously published speculation that the number of pectinal teeth is normally 23–24 (excluding the lost Morroco syntypes of Vachon presumed to have high tooth counts) without commenting on the discrepancy. H. Dastych of ZMUH kindly allowed the first author to study the "female" holotype of B. huberi , and examination reveals that it is not an adult female at all, but a juvenile male. Comparison of the holotype of B. huberi with another specimen of B. occidentalis (the holotype of B. ehrenbergi ) did not reveal any measurable variation that could be regarded as a species-level character. We therefore conclude that B. huberi Lourenço, 2001 is a synonym of B. occidentalis and the type locality of B. huberi represents the southernmost record in the the range of B. occidentalis .