(which occurs together with C. aerarium
in sAZ and sTX) can be distinguished as follows(1)
Male: face with silvery appressed pubescence (absent in C. aerarium, hairs dark)
Female: mesopleural surface ridged or wrinkled between punctures; pronotum and scutum with coarse, rather dense punctures, at least anteriorly (C. aerarium: mesopleural surface everywhere smooth between punctures; pronotum and scutum with fine, widely scattered punctures).
Although generally not closely associated with humans, they are found wherever their hosts (Gryllus crickets) are found, which could include close proximity to homes (though not so much as Sceliphron and Chalybion). Chlorion is usually found in open areas such as meadows, overgrown fields, dunes, beach edges, etc., although they may not necessarily hunt in the same habitat as they nest. They are sometimes associated with the Cicada Killer where the ranges of these two wasps overlap, C. aerarium digging burrows off side of the larger wasps nest (O'Brien, 1989).
Late Jul -- early Aug in Michigan
Females mass-provision several serial cells, each containing from 2 to 9 nymphs or adults of Gryllus pennsylvanicus. Prey are transported on the ground, venter-up, with the wasp's mandibles grasping the antennae of the cricket.
O'Brien M.F. (1989) Distribution and biology of the sphecine wasps of Michigan (Hymenoptera: Sphecidae: Sphecinae). Great Lakes Entomol. 22: 199-217.