Found nectaring on wild buckwheat flowers (Eriogonum nudum var. westonii), in a habitat combining adjacent elements of arid desert scrub, sandy wash wildflower beds, riparian, and rocky cliffs/canyons on the east side of the Sierra Nevada.

Referring to various images in this series, I count 10 flagellomeres, and 6 metasomal segments...so I believe this is a female. Yet there are no scopae on the legs or venter. Seems to have the gestalt of a bee to me...perhaps it's a cuckoo?

Unfortunately, none of my images provided a complete view of the wing venation. But, just maybe, the partial views here will be sufficient for diagnostic purposes? (Or perhaps, with luck, it can be placed using characters other than wing venation?)