Extracted from 2017 “Bees of Maryland: A Field Guide” http://bio2.elmira.edu/fieldbio/beesofmarylandbookversion1.pdf
Uncommon nest parasite of summer and fall Colletes bees. Generally smallish and densely arrayed in short flattened and prone hairs creating bold patterns of black and white bands and islands.
Field Marks: ♀♂Lacks long hair. Integument black except legs often red or reddish, rarely with red on base of antennae, head, and thorax (Most noticeable in E. bifasciatus). All visible hair short, flattened, and prone. Abdomen with striking bands of black and white hairs, particularly noticeable on first abdominal segment. Thorax, upper surface, sides of rear edge with two small triangular projections (axillae). Thorax, upper side, pattern of hair often, but not always appears like the classic “smiley face.” ♀Hind legs with same short hair length as other legs. ♂With small, narrow, parallel-sided, bare plate (pygidial plate) with a rounded end at the very tip of its abdomen.
Flight Season: Summer and fall.
Size Relative to Honey Bee: 0.5–0.75X.
Position of Wings Feeding on Flowers: Most of the time up and out at about 45° to the body; appearing narrow-winged as hind and fore wings overlap, somethings closes wings across back if staying in one place for a time.
Location of Pollen Carrying Hairs: None, nest parasite.
Similar Genera: Triepeolus - On average, larger, more common, but lots of overlap between the two genera and almost impossible to tell apart in the field. However, within the two groups a few have species-specific unique characters that can be used for separation, and will be covered in greater detail in a publication at the species level.
Nest: Nest parasite of Colletes.
Flowers: Nectars at a variety of flowers.
- Andrej Gogala