Historical Biogeography and Natural History of Nocturnal Wasps in the Southwestern Deserts with Special Emphasis on the Genus Chyphotes (Hymenoptera: Chyphotidae

Deserts are interesting places due to the large number of plants and animals that live there. Nocturnal wasps are extremely abundant in deserts, but they are difficult to identify and their life cycles are not well known especially the families of Chyphotidae, Tiphiidae (Brachycistidinae), and Mutillidae (velvet ants). In this dissertation, I determine how to correctly identify a particularly difficult group of species that all have black heads from the family Chyphotidae. This is important because these species make up a large proportion of specimens collected. Also, I expanded our knowledge on the distribution of the species of these three families of wasps by conducting a trap-transect study in Joshua Tree National Park catching 22 species of Brachycistidinae based on the collection of 13,960 specimens, 11 species of Chyphotes based on the collection of 1,513 specimens and 35 species of velvet ants based on 8,477 specimens. From this study, three new species of velvet ants are described: Odontophotopsis dalyi Sadler and Pitts, sp. nov., O. odontoloxia Sadler and Pitts, sp. nov., and Photomorphus schoenwerthi Sadler and Pitts, sp. nov. Lastly, I used new molecular methods to determine relationships of the species of Brachycistis, Chyphotes, and Odontophotopsis. These relationships suggest that the species are young, which is contradictory to evidence based on birds and mammals. These relationships also support dates for the inundation of southern California by the Boues Sea Embayment and confirm as hypothesized Baja Inner Peninsular Seaway.