Abstract
Three new species of Perdita (Xerophasma) endemic to the Mojave Desert are described: P. celadona Griswold and Miller and P. vespertina Griswold and Miller from eastern Clark County, Nevada, and P. rhondae Griswold from Death Valley, California. The subgenus is redescribed to accommodate these new species. New distributional records for P. bequaertiana and P. pallida and a key to the species of the subgenus are provided. A well supported phylogeny suggests evolution toward nocturnal foraging expressed in increasing ocellar size and a trend toward totally pale integument. The apparent origin and center of diversity for the group is the eastern Mojave Desert.References
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