Nature of the Lake: Cow Killer

The south’s distinctive Red Velvet Ant isn’t really an ant at all. Photo courtesy of Kenneth Boone.

Cow Killer, Red Velvet Ant, Cow Ant, Eastern Velvet Ant, Mule Killer – it doesn’t matter what you call these bright red and black insects. What matters is that you know they are not ants – they’re wasps – and their stingers pack a wallop.

So don’t be tempted to pick up these “pretty ants” to take a closer look.

Scientists know these insects as Dasymutilla occidentalis.

This wasp lives in the eastern and southern half of the United States, from Connecticut to Florida on the eastern shore and west to Texas and Missouri.

The female Red Velvet Ant is pictured here. She is wingless, and she really does look like an ant. Her mate has two sets of translucent black wings and looks much more like a wasp.

Interestingly, the female that looks like an ant has a powerful sting like other wasps. The male that looks like a wasp is stingless.

These insects grow to about three-quarters of an inch long. They have red heads and bodies, while their abdomens are red and black striped. Red Velvet Ants are covered in black and bright red “fur” that looks a lot like velvet from a normal person’s height. Once you get a little closer, or a lot closer, you will see that the wasp is covered in course hairs.

Females are commonly found in fields and sandy areas and the edges of forests around Lake Martin from late spring to fall, most often during the cooler parts of the day. They feed on nectar and other insects.

The female wasps are called Cow Killers or Mule Killers because of their ferocious sting. It’s not really strong enough to put down a cow, but if a person gets stung, it can certainly feel that way.

These wasps are not aggressive toward people. In fact, they are active, fast runners and attempt to flee when a person gets close. But when caught or stepped on, they will defend themselves with their stingers. Before doing so, they often emit a warning squeak … so if you feel something squirming beneath your bare foot in the summer and you here a squeak, jump fast.

A writer to Walter Reeves who hosts The Georgia Gardner blog, told a funny story about cow killers.  He said as a boy in Enterprise, Alabama, he was sitting on the porch swing with his grandfather when he saw a cow killer. He asked his grandfather, “… Can cow killer can hurt you?” His grandfather said, “Nah, I reckon not. ‘Bout all they can do is just crawl around on you.” So he picked it up and got stung underneath his fingernail. After lots of yelling and running around the yard in pain, he said, “You said a cow killer couldn’t hurt you!”

His grandfather replied, “Cow killer? I thought you said caterpillar!”

Red Velvet Ants are solitary wasps – if you get crossways with one, you don’t have to worry about being attacked by a swarm.

If you do get stung by this wasp, ice on the sting area will help relieve the pain.

When it comes time for female Red Velvet Ants to lay their eggs, they hunt for the underground cells of bumble bees and Eastern cicada killers, and they dig down and deposit their egg onto the insect’s larva. The egg hatches into a white grub that eats the host larva before becoming a pupa over the winter; and then, developing into an adult the following spring.

In addition to their defensive squeaking sound, Red Velvet Ants also make a chirping sound when mating.