Open Access

W. David Sissom

• The genus Vaejovis C. L. Koch in the Mexican state of Sonora is reviewed, based on the examination of numerous specimens from United States collections. Four species are reported to occur there: Vaejovis spinigerus (Wood), V. confusus Stahnke, V. sonorae Williams, and V. decipiens Hoffmann. Distributional information for all four species is updated, and a key is provided to facilitate identification. The subspecies V. spinigerus sonorensis Hoffmann is synonymized with V. spinigerus. The record for V. gravicaudus Williams on Isla Tiburon (Williams 1980) is demonstrated to be a misidentification resulting from atypical variation in the closely related V. spinigerus, which is common on the island. A record for V. waueri Gertsch and Soleglad is considered the result of accidental introduction, because additional specimens have not been seen in the well-sampled Alamos area. It is suggested that the genus is probably more diverse than demonstrated here; several species from neighboring Arizona probably occur in Sonora, and new species may eventually be discovered in the poorly sampled interior.