Andrena (Micrandrena) ziziae Robertson, 1891 (Andrenidae) is a well-known species found in a variety of habitats in the eastern and central United States and adjacent southern Canada. Andrena (Micrandrena) vernalis Mitchell, 1960 was described from five female specimens in the eastern United States and was synonymized with A. ziziae by Ribble in 1968. Recently collected specimens from throughout Minnesota have revealed that A. ziziae sensu Ribble is actually two species, one of which matches A. vernalis. Here, we reinstate A. vernalis as a valid species and describe the previously unknown male. We provide diagnostic characters that separate A. ziziae and A. vernalis, as well as data on the geographic range and floral preferences of both species in Minnesota. Andrena vernalis appears to be restricted to high-quality remnant habitats, making it a species of potential conservation concern. These changes will require that previous work on A. ziziae be revisited to determine if A. vernalis is also present.
Portman, Zachary M.; Lane, Ian G.; Pardee, Gabriella L.; and Cariveau, Daniel P.
"Reinstatement of Andrena vernalis Mitchell (Hymenoptera: Andrenidae) from synonymy with A. ziziae Robertson,"
The Great Lakes Entomologist, vol 53
Available at: https://scholar.valpo.edu/tgle/vol53/iss1/5