At least once every summer, I get an anxious phone call about a giant red ant that someone has found, or a visitor appears at the museum door with an inch-long creature in a jar.

Experience has shown that, even before I see it, I can be confident that the "red ant" is really a female of our largest "velvet ant," Dasymutilla occidentalis. While it does look like an ant, the species is technically a variety of wasp, collectively called mutillids, in which the females are wingless and usually banded with brightly colored short, dense hairs.

At least 40 species of this group occur in Virginia. One interesting feature shared by all is that the more drab males have black wings. They are so dissimilar to females that for a long time, scientists couldn't associate males with females unless they were captured while mating. In many cases, the two sexes were thought to be different species and carried different scientific Latin names.

Since mutillids are solitary wasps and rarely common, little is known about their lifestyles. The males sometimes fly to flowers or to tree sap; females are seen running along in dry sandy places, often near streams.

What we do know is that mutillids are "hyper-parasites" on other kinds of bees and wasps.

This unusual kind of symbiosis relates to the fact that many kinds of wasps capture insects and spiders as food for their young, paralyzing the victims with a sting that does not kill them. The victim is then placed in a cavity, a hole dug in the ground by the mother wasp, or in a mud chamber. An egg is placed on the prey and the chamber closed. The wasp larva hatches and then eats the living food source (thus parasitism), eventually reaching full size, pupating and escaping its brood chamber as an adult wasp.

Female mutillids exploit this cycle by searching out and burrowing into an occupied underground larval chamber and laying an egg of their own on the resident parasitic larva (thus hyper-parasitism), which it then consumes, grows, pupates and emerges as an adult mutillid.

Frequently in the animal world, bright-red colorations serve as a protective warning sign for mutillids, the females of which are provided with surprising stings: nearly as long as the entire insect's body.

Velvet ants should never be picked up with the fingers! Their potential to inflict severe pain has earned them such names as "cow killer" ants. While exaggerated, such names reflect the judgment of those unlucky enough to have learned about velvet ants the hard way.

If a female is found crawling about and a stick is handy, by holding her down one can hear a distinct shrill rasping noise made as a warning to deter any closer encounter.

Hyper-parasitism is a good example of the truth that no matter how bizarre and unimaginable it may seem, every possible way to obtain food has been discovered and exploited by insects.

Correlated Virginia science Standards of Learning: 3.4, 3.5, 3.8b; 4.5a, e, 4.8; 5.5d; LS.4b, LS.5, LS.7c, LS.9, LS.10c; BIO.7a.
Richard Hoffman is curator of recent invertebrates at the Virginia Museum of Natural History in Martinsville.