Observations on the prey and nests of seven species of Cerceris (Hymenoptera: Sphecidae)

Cerceris species are remarkably constant in their prey preferences. Records are presented from diverse localities that confirm prey constancy in five species. An apparent exception is noted in the case of C. crotonella Viereck & Cockerell. A mixed aggregation of C. fumipennis Say and C. californica Cresson is reported, both preying upon Buprestidae and using some of the same species. Nest and prey of C. conifrons Mickel are reported for the first time.