Hylaeus basalis, F, Side, NY, Gravel Pits_2014-07-29-15.29
Hylaeus basalis, the Cinquefoil Masked Bee, is primarily a montane bee ranging through southern Canada into New England and throughout the Rockies of the U. S. (1). H. basalis is a Rosaceae (Rose) specialist, especially on Cinquefoils (Potentilla) (1, 2). They nest in wood, requiring forests for their nesting sites (2). H. basalis prefer to nest in holes just a few inches to about a foot up off the ground, and do not excavate their own cavity, but use holes bored by insects in previous years (3). Like other Hylaeus, they carry pollen internally and are almost completely hairless, resembling ants or tiny wasps with their shiny black integument (skin).
Original public domain image from Flickr