Numbers
Arnett lists 502 species
(1). Most of them in the genus
LasioglossumIdentification
Small to medium-sized bees, usually black or brownish, a few have metallic greenish or bluish highlights
(1).
Life Cycle
Typically ground-nesters, with nests formed in clay soil, sandy banks of streams, etc. Most species are polylectic (collecting pollen from a variety of unrelated plants).
Remarks
A few species are attracted to sweat, and will sometimes sting if disturbed, though the sting is not very painful
(1).
Some species are parasitic, especially the genus
Sphecodes (2)See Also
Some metallic-green halictids superficially resemble
cuckoo wasps (Chrysididae), but halictids lack the sculptured cuticle and the ability to curl up in a protective ball.
Print References
Arnett, family #66 of the hymenoptera, pp. 602-603
(1)