1A Integument either: (a) bicolorous, head and thorax ferruginous (reddish), gaster black; (b) unicolorous ferruginous or orange; (c) unicolorous blackish or dark brown; mandibles six or seven toothed; eye small, maximum diameter less than to slightly exceeding length of first flagellomere; ocelli present, sometimes obscure in small individuals; diurnal, matinal (near sunrise), or crepuscular (near sunset) Go to 2 1B Integument light yellow or brownish yellow; mandibles eight to ten toothed; eye large, maximum diameter much exceeding length of first flagellomere; ocelli absent or much reduced; nocturnal. Or go to Lucid-like multi-access key

	2A Small (head length not exceeding 1.26 mm), uniformly blackish or dark brown, usually with anterior one-third of head paler; erect hairs very reduced on head and thorax (two exceptions); pubescence sparse on head; usually crepuscular or matinal. Or go to Lucid-like multi-access key 2B Larger (head length exceeding 0.83 mm), either bicolorous or ferruginous; usually abundantly hairy, erect hairs numerous on head and thorax, appressed pubescence usually dense on third tergum; diurnal. Or go to Lucid-like multi-access key

Keys after Snelling 1976 and Snelling 1982.

This key uses scripts from Brian O'Meara's Research Tools website. Support has come from the NSF, the Center for Population Biology at UC Davis, and other funding sources at UC Davis.