Based on the key to the subgenera of North and Central America (females) in(2): two submarginal cells; tibial scopal hairs largely simple; integument often metallic blue or blue-green; propodeum (outside of the triangle) roughened by punctures.
all the spp. occur in the US, with one (A. nothocalaidis) ranging into Canada (BC) and 6 into Mexico(1)
Thorp, R. W. (1969). Systematics and ecology of bees of the subgenus Diandrena (Hymenoptera: Andrenidae). University of California Publications in Entomology 52: 1-146.
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