Anthidiellum. ehrhorni (Cockerell)

Anthidiellum. ehrhorni (Cockerell)

This species was described originally from the Mojave Desert, and it occurs in the southern California deserts from Baja California Norte and San Diego and Imperial counties to the Central Valley, Death Valley, and Owens Valley, California, as well as southern Nevada to the north and the Sonoran Desert of Arizona to the east. Schwarz (1928) recorded the species from Prosopis, Lotus, and Stephanomeria, and there are females in the Timberlake collection from a variety of plants characteristic of arid and semiarid regions (see Grigarick and Stange, 1968, for others). However, females have been captured on Larrea by us and by others, while they were collecting pollen, although this does not appear to be a preferred host. California flight records are mostly March and April on the low deserts, May and June on the high deserts and in the northern part of the range. In Arizona, two flight periods are evident, reflecting the spring and summer rain periods (March–April; August–September).