What Is A Cow Killer? Why Are Red Velvet Ants Called So?

Have you heard of a bug called a cow ant? Now that you have, you might be wondering what is a cow killer and what the reason behind its name.

Many people believe a cow killer is an ant, but it is actually a wasp. The reason why they are named so is because of their physical resemblance to worker ants.

They are also called cow killers because their females deliver excruciatingly painful stings and not because these wasps are powerful enough to kill a cow.

Continue reading if you are intrigued to learn more about cow killers and why they are called so.

What Is A Cow Killer
Velvet Ant

What Are Cow Killers?

Cow killers, commonly known as red velvet ants, are wasps with large and hairy bodies.

The female wasps are wingless with a brightly colored (primarily red and black) pile of body hair resembling a working ant.

They are about ¾ inches long and have reddish-orange hair predominantly on the head, thorax, and abdomen.

The male cow killer looks similar to the female but is larger and carries two pairs of dark brown wings.

The female velvet ant can be found scurrying on the ground during warm summer, whereas the male often hovers over flowers for nectar.

Some species of cow killers can also be nocturnal. These solitary wasps also produce a unique warning sound (like squeaking or chirping) if they feel threatened.

The wingless wasp can also give a painful sting if the presence of potential predators threatens them.

Velvet Ant

What Type of Insect Is a Velvet Ant?

All velvet ants come from the Mutillidae family. They are, thus, wasps and not ants, as others mistakenly refer to them.

The word ‘velvet’ is used because the female wasp is brightly colored and without wings, giving them a strikingly velvety appearance.

They are called ants because of their uncanny resemblance to ants.

Why Are Velvet Ants Called Cow Killers?

Many people think that the velvet ants are called cow killers because they have the strength to kill cows. It is, however, not true.

The reason why they are called cow killers is because of the female velvet ant’s powerful sting. It is just a euphemism for the sting being so powerful that it can even kill a cow.

How Bad Is Their Sting?

The female cow killer is a stinging insect capable of delivering extreme pain with a single bite.

The species of velvet ants ranks 3 out of 4(the most painful sting) on Schmidt’s Index of Sting Pain.

They use large stingers as the egg-laying ovipositor but can seriously hurt human skin. Their sting, however, is not toxic or poisonous to humans.

Velvet Ant

What Do Velvet Ants Eat?

The adult velvet ants eat nectar and water from the flowers like milkweed. Some may also feed on insects like flies or beetles.

The larvae feed on the host or its larvae and kill them. The female usually lays eggs in the host’s nest, like bumble bees, beetles, and other wasps.

Do Velvet Ants Fly?

The female velvet ants are wingless and, thus, cannot fly. You can often see them running on the ground or digging in the soil, usually searching for food or a potential host’s nest to lay eggs.

The male has a dark brown pair of wings and can fly around. You can spot a male cow killer hovering over flowers like milkweed because it drinks their nectar.

Where Do They Live?

Cow killer ants can be found around the world. In the USA, they can be spotted in Nebraska, where Dasymutilla occidentalis species of red velvet ants are the most common.

You can also locate them from the east of Florida to Connecticut and the west of Missouri and Texas.

Are They Dangerous To Pets or Humans?

The cow killer ants are not aggressive. However, female ants can give a painful sting to human beings or animals if they feel threatened or unsafe in a situation.

Their sting is one of the defenses to protect the eggs or their own life.

A cow killer’s sting is very powerful, as mentioned earlier, so it is advisable not to disturb or get close to these wasps.

Even though they deliver painful stings, red velvet ants are not dangerous to pets or human beings since their sting is not poisonous.

There have been no reports of any casualties due to their bite.

Frequently Asked Questions

Is a Cow Ant a Wasp?

Yes, a cow killer ant is a wasp, but because of their uncanny resemblance to worker ants, they are referred to as red velvet ants.
They belong to the Mutillidae family and are solitary insects, with males flying to mate with females and the latter laying eggs in a potential host.

Why is it called a cow killer?

It is called a cow killer because of the female red velvet ant’s ability to deliver a painful sting if threatened, provoked, or stepped on. The sting pain is excruciating, but it is not poisonous.
The pain is said to be so powerful that it can kill a cow, but this is just a saying and has no basis in truth.

How painful is the cow killer?

The sting of the cow killers is ranked 3 (4 being the most painful) on the index of Schmidt’s stinging pains.
Thus, the pain caused by a cow killer’s sting can be excruciatingly bad. They should be left alone even if you spot them.

What happens if you get bit by a cow killer?

If a cow killer bites you, expect pain for 30 minutes. However, this is not a regular insect bite pain; it is one of the most painful stings by a wasp, as per research.
The explosive aftereffects of pain may include swelling, boils, breathlessness, dizziness, anxiety, and more.

Wrap Up

Cow Killers prefer to live in open areas like pastures, forests, and lawn vegetation.

However, you can also spot them in urban and suburban areas as they are often seen digging soil or scurrying from one place to another.

So, ensure you do not disturb or step on them because their bite will make you scream.

Reader Emails

The colorful moniker of cow killers has made velvet ants pretty famous, and our readers have often asked us many questions about these bugs related to why they are called so and how cows are related to them.

Below are some of the emails from our devoted readers and their pictures of these beautiful insects.

Letter 1 – Velvet Ant

 

hairy insect
Hi there Bug folks!
I searched all over your website for a hairy insect like this one and didn’t see it anywhere. I found it at the top of a small mountain just yesterday (Sept 10th) in the Bay Area in California. It looks like a huge ant that needs a haircut! Please help me identify this bug. Love your website, this is my 2nd submission! Thanks,
Lyndie



Hi Lyndie,
What a wonderful photo of a Velvet Ant, Dasymutilla sackenii, a flightless female wasp with a painful sting.

Letter 2 – Velvet Ant

 

What is it?
Hello!
I was playing with my toddler in the living room, and this little guy stung me on the hand. I haven’t been able to identify him, and wondered if you could help? We live in Middle Tennessee. I didn’t see it at first, but felt a sudden burning sensation in my hand. A short investigation revealed this critter under a sofa pillow. It’s behavior reminds me of a wasp though there are no wings. It actually moves much like a velvet ant we saw a few weeks ago, but isn’t as large nor as brilliantly colored. The abdomen is yellow and black striped with a red head and thorax. I apologize for the graininess of the pictures! Thanks!
H Davis



Hi H.,
This is most definitely a Velvet Ant which explains the Wasp-like behavior. We cannot determine the species, or even the genus, since the quality of the image is not real sharp. Our first inclination is that it might be in the genus Timulla, but it even resembles some members of the genus Dasymutilla.


Update: (04/02/2008) ID for insects
Hey, my name is Will, this is a list of the ID’s for the velvet ant page. image 11. is definitely Timulla. hope this helps a bit.

Update: Velvet Ant
(07/21/2008) Timulla grotei
Finally! After you helped me identify the species of velvet ant that stung me one summer despite my poor photo, it has been my mission in life to get a better quality photo of Timulla grotei if you should want it. After many failed attempts at phographing this fast-moving wasp, I finally got a lady who was relatively still for my camera. She didn’t smile and insisted on waving those antennae, but here she is… and no stings this time.
Heather



Hi Heather,
While we are impressed with your determination, and honored that you felt it was important enough to provide What’s That Bug? with a sharper image, we think you have set too low a goal for your life’s mission. Now that this milestone has been accomplished, we are confident you will accomplish truly great things. Thanks again for providing us with a clear image of Timulla grotei from Tennessee.

Letter 3 – Velvet Ant

 

Unknown Ant July 11, 2009 We found this ant in West Salem Oregon. It was found along a dirt road and has lasted for about 45 days and is still alive in a jar with holes in the lid. I have looked everywhere for some clue as to what it is and can not find anything about this ant the closest that I can find is the cowkiller ant or the velvet ant. Could you help me find out what this ant is? The ant when we first got it had yellow “hair” it has now started to burrow in the dirt I have in the jar and so it has turned brown from the dirt. Robert Henry Salem Oregon USA
Velvet Ant
Velvet Ant
Hi Robert, The Cowkiller is one distinctive species of Velvet Ant in the genus Dasymutilla.  Your specimen is a related species in the same genus, possibly Dasymutilla aureola.  We will try to get a second opinion from Eric Eaton on the species identification.  Female Velvet Ants are flightless wasps with a painful sting.  The winged males do not sting. Update from Eric Eaton Daniel: Your species ID of the Oregon velvet ant is correct.  The “blockhead” appearance is pretty diagnostic. Eric

Letter 4 – Velvet Ant

 

Velvet ant in the napkin drawer? April 10, 2010 Hello again, I was very, very surprised to find this little guy hanging out in our napkin drawer today. There isn’t any food (or theoretically other prey insects) in the drawer, it’s middle in height, and we haven’t brought in any plants to that room recently, so how she got there is a mystery. And a potentially disturbing one if I am right in my assumption that she’s a velvet ant/cow killer. Is that what it is, or is there something else which might have a better reason for being there? I was sorely tempted to squish it for fear of its sting, especially if it’s getting into such unsuspecting places, but I let it go instead (as pictured). Stephen C North Carolina
Velvet Ant
Dear Stephen, We are not even going to attempt to speculate how this Velvet Ant got into your napkin drawer, but you did correctly identify it.  It is not a Cow Killer, Dasymutilla occidentalis.  Based on photos posted to BugGuide, in our mind it most resembles Dasymutilla vesta, which has no common name but the general family name of Velvet Ant.  We are certain she is much better off released than she was in your napkin drawer.
Velvet Ant

Letter 5 – Velvet Ant: Dasymutilla aureola

 

fuzzy ant? Location: Nike Missle Site in California June 7, 2011 9:45 pm hi, this thing was sighted at the Nike Missle Site yesterday (6/6/11) in California is it a giant fuzzy ant or something? Signature: erin nicole
Velvet Ant is Dasymutilla aureola
Hi Erin, This is a flightless female wasp in the genus Dasymutilla, commonly called a Velvet Ant.  There are several species in California with very similar markings and coloration.  Alas, we are boarding a plane in a few hours and we cannot at this time provide you with a species identification for your Velvet Ant.  Velvet Ants should not be handled as they are capable of delivering a very, very painful sting.

Letter 6 – Cow Killer

 

Flaming red velvet ant Location: western North Carolina July 24, 2011 7:48 pm Hi Bugman, Our family are huge fans of your site and use it often to find out about all sorts of insects. This one had us truly stumped. We had never seen anything like it in western North Carolina. She (as we found out here) obviously looked very dangerous so we were careful not to touch when we scooted her gently into the jar to photograph her. Wow am I glad we did! I logged in here ready to ask ”What’s that bug?” And found the article on the top five and discovered this velvet ant aka cowkiller. Now we don’t know what to do with it. We have 3 small children and, of course, their safety is all we really care about. How do we handle getting rid of her carefully? Signature: Emily – concerned mom
Cowkiller
Hi Emily, We are thrilled to read that you heeded the warning sign of aposomatic coloration and that you were able to quickly self identify this magnificent Dasymutilla occidentalis, commonly called a Cow Killer, using our website.  In our opinion, you should release her, but how far from the home might be a dilemma for you.  Though your children are young, we hope that they were included in the research process and that you instructed them that they might get stung if they try to pick up a Velvet Ant of any species.  The habitat of the Cow Killer, according to BugGuide, includes “Meadows, old fields, edges of forests” so you might consider releasing her in some open space nearby that would suit her needs.  The life cycle of the Cow Killer is quite interesting.  According to BugGuide, the female Cow Killer:  “Invades the nest of bumble bees, especially Bombus fraternus. Female searches for bumble bee nests, digs down and deposits one egg near brood chamber. Larva of the Dasymutilla enters the bumble bee brood chamber, kills those larvae, and feeds on them. Larva pupates in the bumble bee brood chamber.”  We have always been intrigued by the origin of the name Cow Killer, and back in 2010, a comment from 22AGS was posted to our site that provided this anecdote:  “In south Georgia in the early ’60s, farmers used to tell me that this wasp got its name by getting into the cloven hoofs of cows and stinging them there. The cow would then run madly off and sometimes be injured or fall, breaking it’s leg. Thus the name, as the lame cow would then have to be put down.”  That posting later inspired this comic that was created by one of our readers.

Letter 7 – Velvet Ant

 

Subject: Big red looking ant. Location: Kingsport, Tennessee, USA April 10, 2015 2:04 pm I fould a red/scarlet ant looking insect on my porch. It has black and white stripes on the bottom of it. It’s about the size of a fingernail. It’s spring time. I have never seen anything like this insect before. I don’t know if it’s an ant or not. I would really appreciate it if you could answer my question. What is it? Thank you. Signature: Ashley
Velvet Ant
Velvet Ant
Dear Ashley, This is a Velvet Ant, a flightless female wasp that is reported to have an extremely painful sting.  Based on this BugGuide image, it might be Dasymutilla scaevola.

Letter 8 – Velvet Ant

 

Subject: Red ant locking bug with black legs Location: Corona, CA April 10, 2016 11:14 pm I found this little bug yesterday in the Cleveland National Forrest, Corona, CA. Can you tell what is it? Signature: Peter
Velvet Ant
Velvet Ant
Dear Peter, This is a flightless female wasp known as a Velvet Ant and she is reported to have a very painful sting.  Your Velvet Ant is in the genus Dasymutilla, possibly Dasymutilla aureola pacifica based on this BugGuide image, though we suspect dissection of the genitalia may be the only way to properly determine the species.  The species may be identified, according to BugGuide, because “Females (wingless): Covered with red vestiture; thorax as broad as long, and the head is broader than the thorax.”  Perhaps it is the camera angle, but the head on your Velvet Ant does not appear to be broader than the thorax.  Perhaps based on this BugGuide image, your Velvet Ant might be Dasymutilla vestita.  We include the Velvet Ant on our Big Five link of “Bugs” that may result in an extremely painful and/or possibly deadly encounter, though that deadliness is far more likely to occur in the “Bug” than the human.

Authors

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  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

13 thoughts on “What Is A Cow Killer? Why Are Red Velvet Ants Called So?”

  1. This individual actually belongs in the genus Pseudomethoca, due to the shape and size of the thorax relative to the head.

    Reply
    • Cow Killer is generally a common name that refers to one species of Velvet Ant, Dasymutilla occidentalis, and it is one of the species with the widest distributions. It is also one of the larger species. See BugGuide for additional information on the Cow Killer.

      Reply
  2. Found one in my pocket a few minutes ago, am now the proud owner of my first velvet-ant sting. :V

    I’m in south-east Alabama, for reference

    Reply
  3. I found one of these “cow killers” on my lawn. I don’t believe in relocating wasps, scorpions, black widows or any noxious and potentially dangerous insects or arachnids. I don’t even relocate raccoons and rattlers unless one considers shooting and dumping their dead bodies into the dumpster “relocating.” So I ground this velvet ant into the soil with my boot heel. Besides, bumblebees are disappearing, so killing one of their main enemies is a good thing.

    Reply

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