DIGITAL FIELD GUIDE: WASPS (Order: Hymenoptera)
Poecilopompilus sp.
<-- from Key Location 22a
Identification features: All specimens collected from the Gardens are male, but presumably the females occur in there as well. The males are about one half inch long, with narrow bodies. Overall color is yellow, but they are heavily accented with amber and brown, particularly the abdomen which is ringed with stripes of all three colors. Poecilopompilus is a spider-wasp, and—though its coloration is more suggestive of a paper wasp (Polistes)—its hind legs are long, sprangling out from its body, and have lots of spines on them. There may be two species, or there may be significant variation within one species. One form’s thorax is black with a yellow vase pattern, the other has its thorax brown with the same yellow vase pattern. Both forms have brown eyes with inner margins outlined in wide yellow bands, triangular-shaped pronotal lobe outlined in yellow, and, the males at least, have long, golden-yellow antenna.
Nesting habit and prey: Not much is known about this wasp. All the images and specimens collected are of males. Generally males emerge before females, are smaller than the females, and do not participate in nest building or provisioning. Poecilopompilus is a solitary wasp, so a female builds and provisions her own nest. She excavates a burrow in the ground and provisions it with spiders. She hunts for suitable prey, stings it, paralyzing but not killing it, then drags it back to the nest. She stuffs the spider into the brood cell, lays one egg upon it, and seals the nest. When the wasp larvae hatches, it eats the paralyzed spider, molts, pupates, and emerges as an adult wasp to begin the cycle again.
Poecilopompilus as pollinator: Both males and females visit flowers to sip nectar for their own sustenance. They have short tongues so they visit plants with shallow, open flowers. Males have been observed nectaring on mortonia and soapberry.
