The red velvet ant is, in fact, a wasp. Although the female is wingless and looks very much like an exotic ant, there is one obvious difference. The antennae of ants is jointed, or elbowed and velvet ants have straight, or at most curved, antennae. The two are closely related, sharing many other features, although ants have a unique body structure between thorax and abdomen, while wasps have the well known narrow waist.
The species that stung me is a female Dasymutilla vesta, quite common in North Texas and sometimes mistaken for the kind that is commonly called cow killer because of its painful sting. The nasty stinging species is Dasymutilla occidentalis. D. vesta does not have a very painful sting, and although a small swelling arose immediately it was gone in an hour. The following day there was a small red mark and firm lump under the skin but no pain or swelling. The male velvet ant does not sting, but sometimes uses a vestigial stinger as a bluff.
Velvet ant life cycle
The males are winged and somewhat more flamboyant than the females, which have no wings, live in burrows and search the ground for places to lay eggs. The prime place to lay velvet ant eggs is the nest of a ground nesting bee or wasp, with larvae that have finished the feeding stage and are just starting to pupate. The determined female velvet ant will dig into the nest and find a healthy pupae. Then she will cut through the hard outer skin and lay an egg. When the egg hatches, the larvae of the velvet ant will eat the flesh of the pupating host. Having killed the host the velvet ant larvae will then spend the winter snugly in the tunnel the bee created and emerge in late spring to feed on pollen and nectar, find a mate and start the cycle again. Some species of velvet ant are parasites of fly or beetle larvae.
Control of velvet ants
The velvet ant prefers bare ground, which is also the preference for the tunnel-boring bees and wasps. They are solitary insects, except for mating, so there is no nest. They are not regarded as a crop pest or a nuisance, so there are no specific control measures in place. They are less frequently found in grassy areas, so the best way to avoid an encounter with the velvet ant is to sow grass seed in your yard and steer clear of bare ground. You probably only need to avoid these insects if you are sensitive to stings. Otherwise, it might hurt a little but there is no known long-term effect from a sting. This variety of wasp is not an aggressive species and will run before they sting. The sting is used only if the wasp is threatened, or caught in clothing.
The taxonomy of the velvet ant.
Ants, Bees, Wasps and Sawflies (Hymenoptera)
Ants, Stinging Wasps, and Hornets (Vespoidea)
Velvet Ants (Mutillidae)
There are about 8,000 species of velvet ant worldwide.
Bessin, R., University of Kentucky College of Agriculture. Velvet Ants. Accessed May 13, 2011.
Colorado State University. Colorado Insects of Interest, Velvet Ants, Accessed May 13, 2011.
The Animal Web Guide. Ant Facts and Pictures. Accessed May 13, 2011.
Iowa State University. Bugguide. Accessed May 13, 2011.
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