Hylaeus crabronoidesIslands: Hawaii
Locations: Hawaii - (KFU, Olaa Small Tract, Volcano)
Habitats: Montane wet forest
Plants: Cheirodendron, Myoporum
Xerces: No info.
Insects of Hawaii: Very small elongate bees with clear wings. Male with three separate large yellow facial marks, yellow marks on the pronotallobes and at the sides ofthe collar, and the basal third of the hind tibiae yellow. Female with unique swollen frons and unique elongate mesosoma. See remarks in full text for comparison with sister species H. specularis. Males are distinguishable from H. specularis by the rather thick head and lack of an impunctate area above the antennal socket.
Hylaeus crabronoides was described from a few females taken at Kilauea, Hawaii, at 4000 ft. The very small, distinctive females (forewing length of type, 3.7 mm) have unique features: frons greatly swollen with the fovea not reaching the level of the lateral ocelli; and a narrow, elongate body with the mesosoma depressed such that the scutum, scutellum, metanotum, and anterior area of the propodeum are almost in the same horizontal plane. It is closely related to H. specularis, in the company of which most of the recent specimens have been collected. Females are easily distinguished by the swollen frons, whereas males are told by the unusually thick head (about half as long as wide in dorsal view, measured from the acme to the center of the occiput) and by the punctate area above the antennal sockets (versus smooth and shining). Both sexes can be separated from the much more common H. dumetorum; males by the arched scape, and females by the more lustrous upper frons and vertex.
Insects of Hawaii Volume 17
Hylaeus near military lands