Circle X Ranch, Santa Monica Mountains Nat. Rec. Area, Ventura County, California, USA
July 7, 2010
Three seconds after previous image in series, the female (above) seems to have had second thoughts about a quick exit from the flower. And the male has his mid-legs on her abdomen, and his fore-legs raised up and ready to pounce!
Couplets in keying these bees to genus appear here
. The males right wing came out better here than in other images I posted of these bees from that afternoon. In particular, some key characters leading to Perdita
are visible in the wing venation: the two submarginal cells; the marginal cell with apex separated away from wing margin; and the stigma with intersection with wing margin longer than that of the marginal cell. You can also see arolia
are present between the tarsal claws (females left hind leg, below her abdomen, and males left front leg...over his head!) The apparent lack of "Abdominal terga with sharply defined yellow or white integumental markings" is the only discrepancy between between the keying process applied to the bee in this other post
vs. these bees. However, from the overall gestalt, and the fact that all these bees were observed on the same plant species, in the same vicinity, and on the same afternoon...I'm assuming they're the same species (let alone genus).