DIGITAL FIELD GUIDE: WASPS (Order: Hymenoptera)
Bicyrtes sp.
<-- from Key Location 17b
Identification features: There are at least two kinds of Bicyrtes in the Gardens, and they look very much alike—Bicyrtes ventrailis and Bicyrtes viduatus. These wasps are about three-quarters of an inch long, without pubescence (hairs), and boldly colored black and yellow. The abdomen is black with yellow bands that do not quite meet in the middle. The thorax is black with various yellow accenting, the most noticeable of which is a “smiley face” pattern. Bicyrtes viduatus has a darkened patch on the leading edge of her front wing. In entomology speak, the first submarginal cell is darkened. Bicyrtes ventralis does not have this darkened patch.
Bicyrtes is a sand wasp. Sand wasps are robust, brightly colored, and fast, agile fliers. You will find them patrolling around nest areas that are often along sandy edges of the Garden paths. They fly low, watching for intruders and stalking prey. They also hover around flowers hanging motionless in the air except for wings moving so quickly they make a noticeable buzzing sound. In fact, you might locate the wasp by hearing it before you actually see a bright streak of yellow zip past you.
Nesting habit and prey: Their common name—sand wasp—describes their nesting habit of digging a shallow burrow in sandy soils. Although they are solitary, they tend to nest in aggregations, perhaps because appropriate soil conditions are relatively scarce. The female Bicyrtes builds and provisions the nest. After she digs the burrow, she hunts for prey—immature stink bugs, leaf-footed bugs, and assassin bugs (Pentatomidae, Coreidae, Reduvidae).
Bicyrtes as pollinator: As an adult, Bicyrtes feeds on flower nectar. She has a long tongue and is not restricted to shallow flowers. She has been observed nectaring on mortonia, desert willow, Texas kidneywood, butterfly bush, and soapberry.
