Article for July - August 2009
For Wildlife Watchers: Red velvat ant
by Rob Simbeck
photography by Phillip Jones
Naming animals is a provably inexact art. The koala bear isn’t a bear at all; it’s a marsupial. The firefly isn’t a fly but a beetle. A killer whale isn’t a whale, a nighthawk isn’t a hawk, and the common trait that links crayfish, jellyfish and starfish is that none are actually fish.
We all know where this is going. The red velvet ant isn’t an ant; it’s a wasp. The females do pretty good ant imitations, though. Three-quarters of an inch long and wingless, their black bodies tufted on the thorax and abdomen with dense orange-red hair, they look amazingly like very big ants. Differences like straight rather than elbowed antennae aren’t enough to undo the deception.
But wasps they are, and, like other wasps, they can inflict repeated stings that pack enough wallop to spur their common nickname: cow killer.
Red velvet ant - Dasymutilla occidentalis
Description: 3/4 of an inch long, black with tufts of red/orange hair. Large and solitary.
Range and Habitat: : Sandy open soils; fields, pastures; much of S.C.
Reproduction: Parasitoid, in that female lays eggs on host—pupa of ground-nesting bee or wasp.
Viewing Tips: Sandy soils, particularly fields and pastures, can be especially promising.
“I had heard from others who had been stung by a velvet ant that ‘it hurt so bad for about twenty to thirty minutes that I just wanted to die and get it over with,’ ” says Don Manley, professor emeritus at Clemson University. “I had worked with them for over twenty years before I was finally stung. I concur with the above description. I have not been stung by a velvet ant since—I will not be stung by a velvet ant again.”
Red velvet ants are not normally aggressive, and if their bright coloration doesn’t warn away potential predators, they can produce a squeaky chirp also designed as a warning. If escape is impossible, though, they’ll prove they’re all wasp. Perhaps not surprisingly, Manley, whose work with velvet ants extends back forty years, has not found a single predator for the red velvet ant.
In this species, males look like females, with the addition of black wings and the absence of a stinger. Still, says Manley, “The males have an elaborate stinging behavior that’s very convincing. It can certainly make you think you’re being stung. I’ve collected them, especially early in my career, and I’ve let them go at times, thinking I was being stung.”
The male’s wings are used in seeking out mates, with both vision and pheromones thought to play a part. Both sexes produce the squeak during the mating process.
Fertilized females dig through the soil and lay eggs singly on the outside of the pupa or prepupa of a ground-nesting bee or wasp. The velvet ant’s outer layer is tough enough to be resistant to the stings of the host wasp or bee.
“When the egg hatches,” says Manley, “the velvet ant larva begins eating the host. Since the host is in a ‘resting’ stage, it has no defense.”
The larvae pupate inside the host nest, growing to full size in a matter of days. Some emerge in summer, while others overwinter in a pupal state.
There are approximately 150 North American species of Dasymutilla, the genus of red velvet ants to which our red velvet ant, or Dasymutilla occidentalis, belongs, with most found from the desert Southwest through Mexico into Central America, and 10,000 species worldwide. Red velvet ants, found from Texas and Oklahoma through the Southern states and into New England, are loners and are generally found singly in open, sandy areas in most parts of South Carolina. They are diurnal and are most active when the temperature is between 70 and 96 degrees.
“While the species may not be the most common in South Carolina,” Manley says, “it is certainly the most conspicuous. When people talk about velvet ants, at least in the Southeast, that is the species to which most are referring.”
This is, says Manley, “one of the later-emerging species in South Carolina. I usually do not see them until at least late June, sometimes early July.” They remain active until September or early October, and some dig into the ground to overwinter in a quiescent state.
The adults feed largely on nectar and so can often be found in pastures and fields. It’s that proximity to domestic animals that gives them their common names of cow killer and mule killer. Manley, though, has not found an instance of a red velvet ant’s sting being responsible for the death of an animal of any kind. That doesn’t for a minute lessen his respect for their sting.
“I was being careful,” he says, “and the one that stung me just barely got me. But I’ve worked with bees, ants and wasps my entire career, and I’ve been stung many times by many different things, and nothing even comes close.”
He reports, reassuringly enough, that there were no lasting effects, although the knot on his thumb lasted for the better part of a month.
Nothing in the sting has diluted his appreciation for a creature that is part of a group he finds “fascinating.” They’re part of the natural landscape worth looking at more closely—although with the respect their formidable defensive abilities merit.
Rob Simbeck is an award-winning free-lance writer living in Nashville, Tennessee.
© 2009 South Carolina Wildlife Magazine, July - August 2009 - www.scwildlife.com