Velvet Ants (Cow Killers): Sting, Identification and Control

Most people meet one on a hot August afternoon, racing across a sandy patch of lawn. Below: identification, what it is doing there, how bad the sting really is, and our analysis of where and when velvet ants are recorded.

Velvet ant at a glance

What is the velvet ant?

Velvet ants are wasps. UF/IFAS counts about 8,000 species worldwide in roughly 230 genera, and somewhere around 400 to 500 in North America, mostly in arid southern and western regions: UF/IFAS gives about 435, the Missouri Department of Conservation nearly 500. The name comes from the females, which lack wings and are covered in coarse hair, so they look like hairy ants.

Velvet ant or real ant?

The waist is the quickest field check: UF/IFAS notes that female velvet ants lack the petiole nodes present on all ants. If you have ants rather than velvet ants, our ant identification guide takes it from there.

Male and female velvet ants

The sexes look so different that entomologists often cannot match a male to its species unless the pair is caught mating, UF/IFAS explains. Males have wings, dark and translucent in the cow killer, and look more like ordinary wasps. They cannot sting. Males are not always the smaller sex: in a south-central Florida study cited by UF/IFAS, males were heavier than females in seven of 13 species.

What do velvet ants do?

They raise their young on other insects’ young. University of Arkansas entomologists describe the female entering the burrow of a ground-nesting bee or wasp and laying an egg near each larva or pupa; the velvet ant larva hatches, immobilises and eats its host, and develops in the host’s nest. UF/IFAS adds that they mostly attack the hard, late stages, such as mature larvae, pupae and cocoons. MDC notes she may stay in the nest for several days.

• Cow killer hosts: MDC says the eastern velvet ant parasitises bumble bee nests.
• Other species use other hosts, including cicada killer wasps, according to MDC.
• Adults of both sexes drink nectar. Arkansas notes males are most often seen at flowers, while females run over the ground searching for nests.

So a velvet ant on your lawn is a signpost: it is there because host nests are there.

What attracts velvet ants?

The nests of their hosts, and the ground those hosts like. MDC finds them most often in open, dry, sunny, sandy places such as lawns and cemeteries. Arkansas describes females running over grassy fields with sandy soil on hot summer days, and crossing lawns and driveways in towns as well as the countryside.

In practice, a yard with bare, sunny, well-drained patches and a population of ground-nesting bees is the yard that gets velvet ants. They have no nests of their own, Arkansas notes, and nothing inside a house is food for them.

Where and when velvet ants are seen

Our analysis of iNaturalist research-grade records found 18,035 US records of the cow killer and 52,529 of velvet ants overall. To compare states fairly we used records per 10,000 of all observations made in each state, since raw counts track how many people are recording.

The cow killer is a southern and eastern insect. Mississippi leads at 10.1 records per 10,000 observations, then South Carolina at 9.95, Louisiana at 8.57, Oklahoma at 8.48 and Georgia at 8.29. Texas has the most raw records, 2,951, but a lower rate of 2.67. We found no cow killer records at all in Arizona, California, Nevada or Utah. That does not mean the West lacks velvet ants: UF/IFAS notes that most North American species live in arid southern and western areas, so the red velvet ant a Phoenix homeowner finds is a different species.

Our seasonality index adjusts for how many people are out recording each month, with 100 as the yearly average. The cow killer is a high-summer insect: it sits at 10 or below from January to April, climbs through June, and peaks in August at 393, nearly four times its usual share. July to September holds 79 per cent of all cow killer records, and August alone 34 per cent. Velvet ants as a group have a broader season, peaking at 246 in August. The cow killer peak comes a month after the bumble bee peak in July.

What happens if a velvet ant stings you?

It hurts a great deal, briefly, and it is very unlikely to be dangerous. The Missouri Department of Conservation calls the sting excruciating, and the stinger extraordinarily long. Texas A&M AgriLife says it is usually much more painful than a bee sting, but that a person is unlikely to get multiple stings. MDC quotes the naturalist Edwin Way Teale, stung as a boy while holding one: the effect was like a series of powerful electric shocks following each other in quick succession.

How bad depends on the species, which is where some sources go wrong. NIEHS says the cow killer’s sting is about like a honey bee’s in intensity. Justin Schmidt’s ratings, published in Toxins in 2019, disagree for the large species: he rated Dasymutilla klugii, which he lists as a cow killer velvet ant, at 3, against 2 for a honey bee. Smaller species were milder: 2 for Dasymutilla gloriosa, 1 for the little velvet ant Dasymutilla thetis, 1.5 for a small nocturnal velvet ant.

Compiled by The Pest Control Brief from Schmidt, Toxins 2019, Table 1, and UF/IFAS EENY-378. A higher LD50 means weaker venom. Schmidt’s harvester ant rating of 3 applies to all North American Pogonomyrmex he tested.

Schmidt groups velvet ants with tarantula hawks as insects with extraordinarily painful stings yet almost no vertebrate lethality. If the person stung develops a generalised rash or difficulty breathing, Texas A&M AgriLife says to see a doctor immediately, and CDC’s NIOSH guidance lists severe chest pain, nausea, severe sweating, loss of breath, serious swelling and slurred speech as reasons for emergency care. For anything else, ask a doctor or poison control. Not sure what got you? Our bite identification guide helps.

Can velvet ants kill humans?

No extension source reports it. UF/IFAS states that velvet ants pose no real threat to humans, livestock or domestic animals beyond the accidental sting, and that their venom is not comparatively toxic. As with any sting, the exception is a person with a venom allergy.

Why is the velvet ant called the cow killer?

Because of the pain, and a story. University of Arkansas entomologists say the names cow killer and cow ant come partly from the painful sting and partly from a belief that these ground-running insects could sting a grazing cow on the tongue, making it swell until the animal suffocated. They add that no livestock deaths from this are known to have been recorded. UF/IFAS notes that some species are also called mule killers, for the same reason.

Why are velvet ants so hard to kill?

They are built like armoured cars. In tests by Schmidt and Blum in 1977, it took 11 times more force to crush the exoskeleton of a velvet ant than a honey bee. The body is also rounded, so bites and stings glance off. Arkansas entomologists note the shell is so rigid it is difficult to push an insect pin through it for a collection.

The armour is one of five defences. When distressed, a velvet ant squeaks by rubbing abdominal segments together, can release an alarm secretion, wears warning colours and, if female, stings. The 2018 study by Gall and colleagues in Ecology and Evolution put that package to the test against real predators.

Compiled by The Pest Control Brief from Gall et al. 2018, Ecology and Evolution 8: 5852 to 5862, which also summarises Schmidt and Blum 1977.

Can velvet ants jump?

No. None of the extension or research accounts we reviewed describes a velvet ant jumping. MDC says they usually run on the ground quite rapidly, and that fast, jerky running is probably what people read as hopping. Females cannot fly either; any velvet ant you see in the air is a male, and males do not sting.

What to do if you find a velvet ant?

Leave it alone and let it go about its way, which is exactly the University of Arkansas advice. UF/IFAS says no control measures are necessary, and Arkansas adds that none are warranted because velvet ants have no nests of their own.

• Wear shoes on sandy lawns and bare ground in summer. Texas A&M AgriLife says barefoot walking in infested areas is the most likely way to be stung.
• Teach children not to pick them up. They sting if held or stepped on, MDC notes.
• Move it rather than squash it. Its armour makes it hard to crush; a cup and a piece of card is easier.
• Look at the host, not the velvet ant. Lots of velvet ants means lots of ground-nesting bees or wasps. Those are usually beneficial too; our ground bee guide explains when they are worth managing and how.

Texas A&M AgriLife says effective control measures for velvet ants themselves are limited, and no professional treatment is called for. For the wider family of wasps around a home, see our wasp and hornet identification guide.

Are velvet ants good or bad?

Mostly neutral to good. They cause no damage, MDC says they are not pests, and the adults visit flowers for nectar. Their larvae do kill bee and wasp young, including bumble bee brood in the cow killer’s case, but no extension source treats them as a garden pest. The only downside is the sting, and that is avoidable.

Frequently asked questions

Are velvet ants poisonous?

They are venomous, not poisonous: the harm comes only from the female’s sting. Their venom is weak by insect standards. UF/IFAS gives an LD50 in mice of about 71 mg/kg, against 2.8 for honey bee venom and 0.12 for the Maricopa harvester ant, where a higher number means less toxic. The sting hurts badly, but UF/IFAS says velvet ants pose no real threat to humans, livestock or pets.

Do velvet ants bite?

What people call a velvet ant bite is almost always a sting from a female. Males have no stinger and are harmless. Texas A&M AgriLife says the sting is usually much more painful than a bee sting, and that most stings happen to people walking barefoot or handling the insect. A generalised rash or difficulty breathing after a sting means seeing a doctor immediately.

How big is a velvet ant?

Most US species are about half an inch to an inch long, according to Texas A&M AgriLife; MDC gives half an inch to 1¼ inches depending on species. University of Arkansas entomologists say cow killer females grow up to an inch. Males can be larger than females in some species, a UF/IFAS cited study of Florida velvet ants found.

Are velvet ants rare?

No. Arkansas entomologists say velvet ants are not rare but most people simply do not notice them. Our iNaturalist analysis found more than 18,000 US records of the cow killer alone, most often in Mississippi, South Carolina, Louisiana, Oklahoma and Georgia relative to recording effort, and 79 per cent of them from July to September.

Sources

• University of Florida IFAS Extension, EENY-378, Velvet Ants, Mutillidae (Insecta: Hymenoptera), J. C. Hertz, 2007, reviewed 2025.
• University of Arkansas Division of Agriculture, What’s that bug? Red Velvet Ant, J. Zawislak, A. Jones and W. Haigwood.
• Texas A&M AgriLife Extension, Velvet Ants, ENT-3004, M. Merchant.
• Missouri Department of Conservation, Field Guide: Velvet Ants.
• National Institute of Environmental Health Sciences, Red Velvet Ants, 2015.
• Schmidt, J. O. Pain and Lethality Induced by Insect Stings: An Exploratory and Correlational Study. Toxins 11(7): 427, 2019.
• Gall, B. G., Spivey, K. L., Chapman, T. L., Delph, R. J., Brodie, E. D. Jr. and Wilson, J. S. The indestructible insect: velvet ants from across the United States avoid predation by representatives from all major tetrapod clades. Ecology and Evolution 8(11): 5852 to 5862, 2018.
• Schmidt, J. O. and Blum, M. S. Adaptations and responses of Dasymutilla occidentalis to predators. Entomologia Experimentalis et Applicata 21: 99 to 111, 1977 (as summarised by Gall et al. 2018).
• CDC, National Institute for Occupational Safety and Health, Insects and Scorpions at Work.
• The Pest Control Brief analysis of iNaturalist research-grade records, pulled October 2026.