Numbers
5 genera according to Nearctica: Caupolicana, Colletes, Eulonchopria, Hylaeus and Ptiloglossa
Identification
Yugal lobe in HW longer than submedian cell. Basal vein straight or nearly so. One subantennal suture below each antennal socket. Glossa (tongue) short, bilobed or truncate.
2nd and 3rd submarginal cells are roughly the same size in Colletidae, while 2nd one is distinctly smaller in Andrenidae.
Remarks
Two subfamilies:
Hylaeina (Yellow Faced Bees), slender, black, 10 mm. or less, usually with whitish or yellowish areas on the face. They lack pollen collecting apparatus and resemble wasps; they can be recognized as bees by the branched body hairs. Very common.
Colletinae (Plasterer Bees), more robust and hairy than Hylaeinae; brownish; 3 submarginal cells; second recurrent vein somewhat S-shaped. Less common than Hylaeinae. They nest in the ground and plaster their galleries with a thin transparent film.
Internet References
Cornell University Bee Phylogeny, information on family Colletidae.
