Iuroidea Thorell, 1876

Soleglad, Michael E. & Fet, Victor, 2003, High-level systematics and phylogeny of the extant scorpions (Scorpiones: Orthosterni), Euscorpius 2003 (11), pp. 1-175 : 109-110

Superfamily Iuroidea Thorell, 1876 , new rank

Type Genus. Iurus Thorell, 1876 .

Composition. This superfamily is established here. It includes two families: Iuridae and Caraboctonidae (the latter is elevated here to family rank). Our Iuroidea corresponds to the family Iuridae as treated by Sissom & Fet (2000b), excluding the genus Anuroctonus , which is transferred to Chactidae .

Distribution. Europe, Asia, North America, South America.

Taxonomic history. The taxonomic history of Iuroidea is complicated (see Sissom & Fet, 2000b). Iurinae and Caraboctoninae were treated as subfamilies of Vaejovidae by Kraepelin (1905), then as subfamilies of Iuridae by Francke & Soleglad (1981). Stahnke (1974) created the subfamily Hadrurinae (under Vaejovidae ), which included Hadrurus and Anuroctonus . Stockwell

(1992) recognized family Iuridae with three subfamilies (Iurinae, Caraboctoninae , and Hadrurinae ). Stockwell (1989) and Lourenço (2000a) included Iuridae in the superfamily Vaejovoidea .

Biogeographic history. A significant range disjunction between Old World iuroids ( Iuridae ) and New World ones ( Caraboctonidae , both Nearctic and Neotropical), suggests that this ancient lineage probably existed already in the Pangean times. Francke & Soleglad (1981) indicated that its modern vicariance could be created by a series of events starting from the Jurassic opening of the North Atlantic. The separation and isolation of Caraboctonidae subfamilies between South America and North America could result from the decoupling of the North American and South American plates, which played a prominent role in formation of the Caribbean region in late Mesozoic–early Tertiary ( Rosen, 1976; Francke & Soleglad, 1981).

Diagnosis. Synapomorphies. Ventral edge of cheliceral movable finger with one large denticle; ventral surface of leg tarsus with median row of spinule clusters; stigma oval in shape; chela trichobothrial series db–dt and eb–et found on distal half of finger; patella ventral trichobothrium v 3 found on external surface; Important Symplesiomorphies. Median denticle row (MD) of pedipalp chelal finger arranged in oblique groups; pedipalp chelae exhibits “8-carinae” configuration; dorsal edge of cheliceral movable finger with single subdistal denticle.