Hylaeus ombriasIslands: Hawaii
Locations: Hawaii - (Ahumoa, Kipuka Kalawamana, Puu Waawaa, South Point)
Habitats: Coast and montane dry shrubland and forest.
Plants: Bidens, Chamaesyce, Scaevola, Sida, Tetramolopium, Tribulus
Xerces: Hylaeus ombrias is a coastal and dry forest bee endemic to the island of Hawaii in Hawaii. It is distinguished by its large size compared to other coastal species, and reduced facial marks. It is typically found as scattered individuals, and habitat destruction has caused its range to contract significantly.
Insects of Hawaii: Large bees with dark smoky wings and terga without punctation (unusual for bees of this size). Male with unusual scape, slightly dilated, widest near the middle and smaller at both ends, and with short, plumose hair along the median edge; face with two or three separate yellow marks (in paraocular areas and with or without a mark on the clypeus, no supraclypeal mark), otherwise body and legs black and unmarked; distinguished from the smaller, less melanic, sister species, H. assimulans, by reduced facial marks (none on supraclypeal area, sometimes none on clypeus), lineate to reticulate rugosity often to brow of propodeum, and darker wings. Female black and unmarked, upper frons granular.
See remarks for H. assimulans and H. flavipes.
Insects of Hawaii Volume 17
UH/DOD: Like H. flavipes, this is a basically coastal/lowland species that also occurs in high elevation montane dry forest habitats on Hawaii. Its large size may be an adaptation to feeding on the large pollen grains of Sida fallax and other Malvaceae, which are visited by other Hylaeus but rarely utilized for pollen (Magnacca, unpublished data). During this survey, only a single individual was found, in a rare plant restoration area on Puu Waawaa cone (Figure 10). It was not found at South Point or PTA, where it had been found in moderate numbers previously (Daly and Magnacca 2003), despite abundant flowering of Sida and Bidens at the latter.
Hylaeus near military lands