Butheolus Simon, 1882

Lowe, Graeme, 2018, The genera Butheolus Simon, 1882 and Xenobuthus gen. nov. (Scorpiones: Buthidae) in Oman, Euscorpius 261, pp. 1-73 : 2-4

Genus Butheolus Simon, 1882

Butheolus Simon, 1882: 248 .

Butheolus: Karsch, 1886: 76 ; Pocock, 1890: 121–122 (part); Pocock, 1892: 47; Laurie, 1896: 131; Lönnberg, 1897 b; 194 (part); Kraepelin, 1899: 34 (part); Pocock, 1900: 28 (part); Kraepelin, 1905: 337, 353; Simon, 1910: 77; Hirst, 1911: 462, 464; Birula, 1917a: 164; Birula, 1917b: 55; Werner, 1934:145, 266, 270, 294, 299; Kästner, 1941: 231; Sreenivasa- Reddy, 1970: 18; Stahnke, 1972: 127, 129, fig. 12 (part); Vachon, 1974: 906; Vachon, 1975: 1598 (part); Vachon, 1980: 253 (part); Francke, 1985: 6, 15; Vachon & Kinzelbach, 1987: 92 (part); Sissom, 1990: 97, 101 (part); El-Hennawy, 1992: 97, 101, 104, 114 (part); Nenilin & Fet, 1992: 17; Lourenço & Vachon, 1995: 297; Kovařík, 1996: 177–178; Kovařík, 1998a: 117; Kovařík, 1998b: 105 (part); Fet & Lowe, 2000: 88 (part); Lourenço, 2001: 179; Kovařík, 2003: 137–138 (part); Soleglad & Fet, 2003: 88; Kovařík, 2004: 2–3 , 25 (part); Fet & Soleglad, 2005: 11; Fet, Soleglad & Lowe, 2005: 3, 11, 22, fig. 23 (part); Lourenço, 2005: 26–28; Prendini & Wheeler, 2005: 481; Hendrixson, 2006: 56 (part); Lourenço & Qi, 2006: 91–93 (part); Dupré, 2007: 4, 12, 17 (part); Kovařík, 2009: 23, 31; Hennawy, 2009: 126 (part); Lowe, 2010a: 37, 44; Lourenço & Leguin, 2011: 1; Kovařík & Lowe, 2012: 1–2, 18–23 (part); Kovařík et al., 2013: 4; Yang et al., 2013: 5; Loria & Prendini, 2014: 25, tab. 5; Lowe et al., 2014: 120, fig. 98; Lowe & Kovařík, 2016: 1, 43; Loria & Prendini, 2018: tab. 1.

TYPE SPECIES. Butheolus thalassinus Simon, 1882 , by subsequent designation ( Kraepelin, 1895: 5; Pocock, 1895: 295).

Simon (1882) described B. thalassinus as a new species under Butheolus , but did not explicitly designate it as the type species. In the appendix to the same publication, he described a second new species under the same genus ( B. aristidis ), leaving ambiguity about which was the type species. Later, Birula (1898: 292) transferred B. aristidis to Orthochirus . According to Fet & Lowe (2000: 88), B. thalassinus was established as the type species of Butheolus by subsequent designation of Simon (1910: 77). However, a subsequent designation according to ICZN Art 69.1.1 had already been made earlier by Kraepelin (1895: 5) and Pocock (1985: 295) when they referenced B. thalassinus as the type species of Butheolus , and it was also cited as the type species by Pocock (1900: 28).

DIAGNOSIS. Small buthids ( Kovařík, 2009; Sissom, 1990), adults 24–36 mm in length; carapace strongly trapezoidal, ratio of posterior W/ anterior W 1.9 –2.5, preocular area inclined downwards towards anterior margin, surface densely granular, without distinct carinae; tergites densely granular, tergites I–III lacking carinae or with weak median carina, IV–VI weakly tricarinate with median and paired lateral carinae; tergite VII with broad median carina, two pairs of lateral carinae; posterior margins of sternites III–VI armed with fringe of non-contiguous digitate denticles that are larger in males; metasomal segments nearly uniform in width and depth, robust with granulated carinae, segments II–V densely granular on lateral and ventral intercarinal surfaces; metasoma I–III with 10 carinae, IV with 4 or 6 complete carinae (ventrosubmedian, ventrolateral pairs complete, dorsosubmedian pairs may be complete, dorsolateral pairs weak or incomplete), V with 2 complete carinae (ventrolateral pairs); ventrolateral carinae on metasoma V without enlarged lobate dentition; telson with slightly elongated ovoid vesicle, with or without a blunt subaculear tubercle, aculeus shorter than vesicle; pectines with fulcra; hemispermatophore with flagellum separated from a 3-lobed sperm hemiduct, basal lobe a small, narrow, hook-like process; chelicerae with characteristic buthid pattern of dentition ( Vachon, 1963), two denticles on ventral aspect of fixed finger; pedipalps orthobothriotaxic, type Aβ ( Vachon, 1974, 1975), patella with d 3 internal to dorsomedian carina, chela manus with V 2 not strongly displaced internally, V 1 – V 2 axis nearly collinear with long axis of chela, chela fixed finger with db on proximal half of finger between esb and est, it near tip; pedipalps short, chelae small with carinae reduced or obsolete, dentate margins of fingers armed with 6–7 (rarely 8) non-imbricated linear subrows of primary denticles; subrows flanked by mid-row internal and proximal external accessory denticles; movable finger with 3 enlarged subdistal denticles; males without recess or scalloping of dentate margins at base of pedipalp fingers, with chela manus narrower than females; tergites lacking macrosetae; tibial spurs present on legs III–IV; basitarsi I–III with regular series of long macrosetae on retrosuperior, retroinferior and inferior margins; ventral surfaces of telotarsi with paired rows of macrosetae; prolateral and retrolateral tarsal spurs present on all legs; moderate sexual dimorphism in setation, macrosetae on carapace, pedipalps, legs, sternites and metasoma longer in females than males.

REMARKS. Sexual dimorphism in setation is apparent in Butheolus , but is not as pronounced as it is in Neobuthus Hirst, 1911 , in which males usually bear much shorter, stouter macrosetae than females ( Kovařík & Lowe, 2012).