Genus Paruroctonus

PAR-you-ROCK-ton-us, or PAIR-you-ROCK-ton-us.

3 species groups, further subdivided into 7 "microgroups".

30 species.

Adults range in size from 30 mm (Paruroctonus luteolus) to about 70 mm (several spp.).

Sand-dwelling species are distinguished by a row of setae (hairs) on the tarsal segments of the legs. This row of setae is called a bristlecomb and is in most species. Otherwise, they have large, robust pedipalp chelae (hands), and usually a slender metasoma (tail). An important character on the metasoma is the dorsal carinae (ridges) do not terminate with an enlarged granule or spine (seen in Vaejovis and other vaejovid genera except the punctipalpi group of the genus Vaejovis). The median eyes are typically large.

Paruroctonus are found in all the western states west of and including Texas, New Mexico, Colorado, Wyoming, South Dakota, and North Dakota, and into SW Canada and northwestern Mexico. The greatest diversity is in the southwestern deserts.

Most species are restricted to active sand dunes, but a few species occur in most other habitats. Paruroctonus silvestrii is found from coastal dunes to mountain pine forests in California and Baja California; P. boreus is the widest-ranging vaejovid scorpion and is found in many habitats from northern Arizona to southern Saskatchewan, Alberta, and British Columbia, Canada.