Small, overlooked, and rarely detected primarily fall species.

Field Marks: ♀♂Tiny size, without noticeable body hair. Face, wider than long. Wings, 2 submarginal cells. Abdomen with no noticeable pale hair bands/patches or pale markings of any kind. ♀Body, including face, entirely black. ♂Clypeus bright yellow or mostly bright yellow, remainder of bee all black with the exceptions a dot of yellow on the pronotal lobe on the thorax near the head and yellow on the ends of legs, which often extends to parts of the tibia.
Flight Season: Fall
Size Relative to Honey Bee: 0.5X
Position of Wings Feeding on Flowers: Completely overlapping
Location of Pollen Carrying Hairs: Hind tibia and basitarsus
Similar Genera: Hylaeus - ♀Has yellow/white markings on face between eye and clypeus; carries no external pollen. ♂Entire lower face often yellow/off-white. Calliopsis - Markings quite different. Perdita - Most common species are restricted to sandy locations and contain light-colored marks on the abdomen. Panurginus - Spring species, flight period does not overlap. Most of the Other Genera that are Small Black Bees - Have 3 submarginal cells and noticeable, though possibly restricted, patches/bands of pale hairs.
Nest: Ground, flat, open bare soil
Flowers: Most species are composite specialists

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