Foraging Ecology of the Bee \u3ci\u3eHabropoda laboriosa\u3c/i\u3e (Hymenoptera: Anthophoridae), an Oligolege of Blueberries (Ericaceae: Vaccinium) in the Southeastern United States

摘要

The anthophorid bee, Habropoda (=Emphoropsis [R. W. Brooks, personal communication]) laboriosa (F.), is a locally abundant, vernal, univoltine species. It flies from February through April in Georgia and Alabama. In these states, females are oligolectic on Vaccinium spp., particularly V. ashei Reade and V. corymbosum L., with Gelsemium sempervirens (L.), Quercus alba L., and Cercis canadensis L. as minor, alternate pollen hosts. Pollen-harvesting female H. laboriosasonicate V. ashei flowers to release pollen, averaging 5.7 buzzes during their average 2.6-s floral visit, which is a handling rate 3 times faster than coforaging Bombus spp. Furthermore, mean floral handling rates of H. laboriosa females at V. ashei are individually more uniform than those of coforaging, polylectic Bombus spp., a hitherto undemonstrated but expected evolutionary outcome of oligolecty. Sonicated pollen accumulates on a ventral cephalic \u22safe site\u22 of both sexes, which is the common site of V. ashei stigmatic contact. Floral probes are strictly legitimate (no robbing). Based upon its relative abundance at Vaccinium spp., phenology, floral handling behaviors and rates, and pollen preferences in the southeastern United States, we conclude that H. laboriosa is an oligolege adapted to species of Vaccinium for its pollen and nectar resources.