Buthacus Birula 1908
Creators: name: Kovařík, František
name: Lowe, Graeme
name: Šťáhlavský, František
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Scorpiones
Buthidae
Buthacus

description: Buthacus Birula, 1908   
(Figs. 1–63, Table 1)  
 Buthus (Buthacus) Birula, 1908: 139–140.   
 Buthacus: Simon, 1910: 74 (in part); Fet & Lowe, 2000: 81–86 (in part, complete reference list until 2000); Kovařík, 2005: 1–10, figs. 1–8 (in part); Kovařík, 2009: 30; Kovařík et al., 2013: 1–4, fig. 5.   
 TYPE SPECIES. Androctonus (Leiurus) leptopchelys Ehrenberg, 1829.   
 DIAGNOSIS. Total length 40–90 mm (except B. villiersi Vachon, 1949 and B. clevai Lourenço, 2001); carapace trapezoidal, in lateral view preocular area not distinctly inclined towards anterior margin, level with or higher than postocular area; surface of carapace conspicuously granular, with only anterior median carinae developed, anterior part of carapace glossy; ventral aspect of cheliceral fixed finger with two denticles; tergites with three carinae of which lateral pair on I and II inconspicuous; pectines with fulcra, hirsute; hemispermatophore flagelliform, capsule with 4 lobes, lobes separated from flagellum, basal lobe small, knob-like; sternum subtriangular; metasomal segments I–III with 8–10 carinae; metasoma II as wide as other metasomal segments; metasoma V with enlarged "lobate" dentition on ventrolateral carinae; telson without subaculear tubercle, with long curved aculeus, longer than vesicle (except B. buettikeri Hendrixson, 2006); all segments of metasoma hirsute, with long setae in both sexes, dentate margin of movable finger of pedipalp with 9–12 rows of granules, each row equipped with one internal accessory granule, and with (B. leptochelys complex) or without (B. arenicola complex) one external accessory granule, 4 terminal and one basal terminal granules present; trichobothrial pattern orthobothriotaxic type A; dorsal trichobothria of femur arranged in β- configuration; pedipalp patella with 7 external trichobothria; pedipalp femur with trichobothrium d 2 on dorsal surface; d 2 of pedipalp patella present; patella trichobothrium d 3 internal to dorsomedian carina; tibial spurs present on legs III–IV but could be reduced or absent on leg III.   
 COMMENTS. Many of the diagnostic characters applied to differentiate Buthacus from other buthid genera seem to be plesiomorphic, so the genus is not strongly supported by derived characters. Thus, Buthacus may be a paraphyletic assemblage of taxa containing several distinct lineages. It is beyond the scope of this paper to completely revise and divide Buthacus.   
 B. agarwali Zambre et Lourenço, 2010 from India definitely does not belong in Buthacus because it differs in the characters cited in the diagnosis above as well as in other aspects of its morphology, mainly in shape of the pedipalp segments. The taxonomic position of B. maliensis Lourenço et Qi, 2007 from Mali is also doubtful. It has a short aculeus, the anterior part of the carapace is probably not glossy, the movable finger of pedipalp has nearly linear rows of granules, and the total length is 29.8 mm.   
 It appears that the most reliable diagnostic character for Buthacus is the presence of 9–12 rows of granules on the movable finger. The only species for which this character is inapplicable is Buthacus williamsi Lourenço et Leguin, 2009 from the United Arab Emirates, described from three females that have 6 or 7 rows of granules on the movable finger. We are convinced, however, that this species does not belong to the genus Buthacus but probably to the genus Vachoniolus Levy, Amitai et Shulov, 1973.
description: Published as part of 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), pp. 1-18 in Euscorpius 236 on page 2