Scorpion like bug in New Mexico
Attached is a photo of a rather large and intimidating “bug”. It has claws like a scorpion, but not the curved tail with the stinger. Instead it has that long thin wiry tail. The tail actually looks like a long piece of wire of stiff hair. Can you tell us what it is? Is it poisonous or harmful to humans? Does it eat other insects? Thanks.
Monte and Mary Kern

Hi Monte and Mary,
This is a harmless Whipscorpion, Mastigoproctus giganteus, also called a Giant Vinegaroon or Grampus. Legend has it that the bite of a Vinegaroon will cause the person to taste vinegar for weeks. Though this is untrue, BugGuide notes that “Although its tail in unable to sting, this creature can spray an acidic mist from a scent gland at the base of the tail when disturbed. The spray is 85% concentrated acetic acid/vinegar, hence the common name “Vinegaroon.” The heavy pinching mouthparts (modified pedipalps) can also inflict a painful bite. Although very unlikely to attack humans, it can certainly defend itself if provoked.” The Vinegaroon is a nocturnal predator with poor eyesight. It feeds on insects, other arthropods, and also, probably, small vertebrates like lizards.

54 Responses to Giant Vinegaroon

  1. kodiyaps says:


    While camping at Caballo Lake State Park near Hatch, NM my family and I came across the biggest and scariest insect that we have ever seen! It was dead (thank heavens) and looked to have floated up onto the shore of the lake. We examined it for a long time and could hardly wait to get back home so that we could find out what it was. Thanks to you and your wonderful blog we have the answer! Our crazy critter was a Whipscorpion. Although I get chills just thinking about it, I am grateful for the discovery because it makes the occasional house roach a bit less disturbing knowing that there are much more intimidating insects, like this one, out in the desert!

    Thanks again for the work that goes into publishing your blog. We’ll be back!

    The Yap Family
    Las Cruces, NM

  2. gilberto says:

    this things are all over my backyard

  3. Debbie says:

    Years ago in New Orleans, a bug crawled into our hous. It was large and looked almost like rubber. The reason that I knew that it was not a toy was that it was still moving. It was about 4 inches long and reminded me of a vinegaroon (I am from New Mexico) but it had no whip tail. It had large pincers and was a dull grey. I gave it to the exterminator and he said he had never seen anything like it and could not identify it. Have you got any ideas?

  4. S. Nuzum says:

    I have seen a few here in Nevada, but they are light brown in color and shine, almost look wet. I have been told they are the larva of the owl moth, is that true?

  5. Teddy says:

    I’m from Washington State and was stationed at Holloman AFB New Mexico when I was in the Air Force. I found one in my lower kitchen cabinet when I was putting dishes away one evening…Scared me to death, didn’t know what it was… My husband swept it out of the cabinet and killed it with a broom… The house smelled of vinegar brine for several days!

  6. Sandra says:

    15 years ago saw one in my kitchen just walking around taking its time. My daughter, 16. yrs old, felt sorry for it. Put it in a jar, took it to her high school science teacher, who identified it. They took it outside & released it. Yucca Valley, CA, 35 miles north of Palm Springs.

  7. CHARLOTTE says:


    • bugman says:

      Though we have not received any documentation of Vinegaroons feeding on Scorpions, we suspect that if a Vinegaroon and a Scorpion encountered one another, the Vinegaroon would be the victor more often.

  8. joey t says:

    I live in casa grande az and I have a nest somwhere under my house there only geting about 2 in long but I don’t know how to get rid of them any ideas there vinegaroons and I have a new born and a 6 year old daughter and I don’t trust them please help

    • bugman says:

      We do not provide extermination advice, especially for beneficial species.

      • Dawn says:

        “Getting rid of” bugs doesn’t necessarily mean exterminating them. Do you have advice on how to repel these bugs that have the ability to inflict painful bites on very young children?

        • bugman says:

          We have no advice on repellents.

          • Dawn says:

            I’ve read that peppermint oil will repel spiders and have a friend that proved it repels mice. Do you know if this might work with vinegaroons? Because if there is no way to make them go away, they’ll be killed. That’s nature. Parents eliminate threats to their children.

          • bugman says:

            We do not know if peppermint oil will repel Vinegaroons.

  9. Rodolfo says:

    Are these in the pet trade?

  10. Mike says:

    Just photographed one of these in central China.

  11. Kenny says:

    I have a pic of a 4 to 5 inch vinegaroon that I just saw on my outside house wall and would like to share.. I live in Silver City, New Mexico

  12. Cindi says:

    thanks for the information. There is one now dead on our front porch in Alamogordo, NM but now know to just redirect them from our door! We also have a spotted egg on our rock in our courtyard that we have been watching for over a week. Believe if it had fallen out of a nest it would have broken. Thinking Quail

  13. Cindi says:

    Loved finding this site! Many years since I received my biology degree but I still respect our environment.

    • Eric Jon Kent says:

      I sure hope that you still respect nature our environment.
      I personally believe that people disrespecting our Mother Earth is part of the reason that we are going to see extreme climate change and the extinction of more and more species of animals which is just dreadful.

  14. Richard New says:

    8/15/2015 I live in Gainesville Ga and at 10:30pm my wife saw one walking across the floor. My children and I was going to try to catch it. But my wife didn’t let us. When we flushed it out it came out her way snd she murdered it. I put it into a s sandwich bag and put it in the freezer to find out what it was. Now I have Thank you. We can put it to rest.

  15. Nick says:

    My 2 mini doxies just flushed one from a corner of our living room in Silver City, NM and apparently got sprayed, since they were sneezing and shaking their heads! I captured it in good condition and returned it to the wild.

  16. dawn boykin says:

    My boyfriend in Bisbee, AZ caught one outside in a jar alive and sent it home with me to show my 18 yr old daughter what one was alive. We are from WA and never saw one before and we are completely fascinated. We decided to name it Kevin and mad a nice tank for it. It eats crickets, grasshoppers, mantis, lizard, roaches, and whatever we put in the tank. We also spray the tank and keep it moist. Kevin sure does like to dig and rearrange the tank. He is awesome!!

  17. mike says:

    a vinegaroon CAN HURT YOU ! stay clear of them

  18. Years again I lived the high Desert, CA. Joshua Tree and Yucca Valley. They resembled the scorpion, with one difference, they were opal almost see through. They said it was also a Vinagerette. They hid in the dark places of our garage. I never touched it and was not threatening me? These also have the bite of vinegar for 2 week’s. Just a little smaller, I saw bigger ones.

  19. No Vinga
    rette, Cant seem to spell it right

  20. Danette says:

    I live in Northern Arizona. My husband got bit by one a week ago. Now he does taste vinegar when he eats and drinks. He vomits up everything he eats. It has made him very sick. I have been doing research on these spiders and everything he is going thrtthrtough is very normal.

  21. April D says:

    Are the dangerous to dogs? We’re from El Paso, tx. We have a 6 month old beagle and we found one in our bathroom! It freaked us out! It was the first time ever seeing one so up close. Our concern is our furry baby. Help!

    • bugman says:

      They have neither venom nor poison, though they do release a weak acetic acid (like vinegar) when threatened.

  22. Odin says:

    Just swept one of my porch -in Silver City, NM.
    To hell with this – the snow and cold of Yooperland is better than this !!! 🙂

  23. Janet says:

    We saw one 2 or 3 years ago at our Church. I took several photos of him, and just let him crawl away; he was outside. Two mornings ago, when my husband went out to the garage, there was another one, shiny, black, probably close to 6″ long, in the corner beside the back door, like he was wanting out. My husband plopped a bowl over him, slid a piece of paper under the bowl, and took him outside to the Red Yucca, where he deposited him. I don’t know whether he will be back or not; it hasn’t been long enough since that occurrence to know. Whenever I go out into the garage, I check that corner, because we had a tarantula in that spot, too. My husband did the same for it.

  24. NACH says:

    Grew up with these guys in the upper Mojave Desert, CA. Our version was large, but more long and slender than the hefty black variety seen in the Sonoran Desert areas. As has been mentioned in at least one previous post, the local type were also very light, indeed often almost translucent in color. We all knew, even as kids, how to distinguish these from the much more significant threat, the true scorpions, of which we had three varieties, the smallest, oddly being the most dangerous. We knew that most of what was said about these creatures was myth and an understandable, although erroneous reaction, to their less than endearing appearance. Perhaps conversely, because of those creepy cool looks, but relatively harmless nature, they were permanent residents in more than a few science classrooms throughout the Mojave Desert communities where I grew up. None the less, growing up in an area that was habitat for a fair percentage of what is poisonous in the U.S. the rule for wild critters of all variety was “step back, leave it alone.”

  25. Dave says:

    i grew up with these critters in South Florida. I know those front claws can break a small stick. I now live in the Southern end of North Florida and discovered they are also here, a dead one fell from my attic stairway as I pulled it down, almost onto me. I do know there are also scorpions up there also but have never been stung by a scorpion. Been stung by nearly everything else however. I agree, don’t harm these critters, they are good to have around us. Don’t play with them either. While you’re trying to be a good nature person, don’t feed the deer either.

  26. John Diehl says:

    First encountered one in the Calif. desert 40 yrs ago with some buddies. Walked into camp and scared me. A buddy in the know laughed and clued me in. Fear gave way to fascination. It exibited zero aggression. Put him in a box where it waited patiently. Wondered how they defended themselves. Couple of hours went by and another buddy pointed out another intruder by the campfire. A scorpion. And of course the inevitable; placing it in the same box as the vinegaroon. It quickly closed the distance grabbing the scorpion which impailed its stinger into its head three times in rapid succession. The vinegaroon’s response was to begin devouring its meal. The scorpion managed two more head shots before dying. The vinegaroon’s head was an angry bright red where it was stung. We wondered how long before it would die. Well it ate till there was nothing left. Released from the box it casually exited our campsite, leaving five grown men with their mouths hanging open at what they had just witnessed. Two thoughts came to mind. Thank god they are not aggressive, poisinous, or large. The other thought was is there any creature on earth as tough as they are. I was and still am impressed by this wonderful creature.

  27. Jeff says:

    We’re in Port orange and I’m 9 years old. me and my grandma were looking
    for one in the yard. we didn’t find one. How do you?

  28. Dave says:

    Look around and under rotting wood, anywhere a scorpion might be. You might want to wear eye protection also.

  29. Jeff says:

    Thank’s bugman and dave

  30. Joy says:

    Enjoyed reading about this creature. I have found them living throughout California. Have seen many in the high desert, where there are lots of scorpions. I have also found them in Oakhurst which is in the mountains close to Yosemite. I have generally let them be. Good to know they are beneficial and hunt harmful creatures. They always run away when I get near them.

  31. carol harper says:

    the crickets have bitten off the tail of my vinegaroon, will it grow back , again, also I do not know what to feed it, as crickets are nasty.

    • A.r. says:

      If it’s not an adult it should grow back in the next molt. If it is it should be ok without the tail. Try feeding Dubia or red runner roaches.

  32. A.r. says:

    They make very good pets, docile and easy to care for. I have one and she’s very nice.

  33. Dave says:

    I would not kill one when found but thinking of it as a pet is a bit of a stretch. I think I’ll stick with the dog!

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