Meet the vinegaroon, the acid-spraying arachnid scuttering around West Texas

Vinegaroon
Vinegaroon (Big Bend National Park)

Visitors to Big Bend National Park in far West Texas are on high alert after one of the parks many insect inhabitants made it’s viral internet debut earlier this month.

On July 14, staff members at Big Bend National Park photographed what appeared to be some sort of unsettling lobster-scorpion hybrid scuttling about the Chisos Basin campground. Naturally, they shared the photo to Facebook.

In a rather informative post, park staff members explained that the fearsome critters, called vinegaroons (Yes, that’s what they’re actually called), emerged from their burrows “in search of food and love” after summer rain swept through the area.

“Vinegaroons are about 3 inches long and relatively benign unless you happen to annoy them,” the post read. “They can pinch with their heavy mouthparts (pedipalps) and shoot a well-aimed spray of 85% acetic acid (vinegar) from the base of their ‘whip’ to protect themselves.”

Needless to say, the post proved quite a conversation starter, spawning hundreds of comments.

“I am going to have nightmares from this photo,” wrote one commenter. “That’s enough internet for today.”

“I have seen some strange bugs in my time that that is the strangest,” wrote another.

One person expressed a keen understanding of the little critters.

“‘Relatively benign unless you continue to annoy them,’ is pretty good description of me,” he wrote.

Many West Texas travelers shared their vinegaroon sighting stories -- one such tourist even took one back home with her, unknowingly of course.

“Found one in our luggage upon returning home from our trip to Big Bend many years ago. We knew it would not harm us, but it was quite the surprise.

RELATED: ‘You’re so pretty. I’m gonna name you Emma’: Baby alligator fished out of Fulshear swimming pool

Known formally as Mastigoproctus giganteus, Texas Vinegaroons are arachnids and distant relatives of spiders and scorpions. They possess long, thin tails -- hence their common name, “whip scorpion.” They’re nocturnal and can’t see well. Using their forelimbs to sense vibrations, they hunt millipedes, scorpions, cockroaches and other invertebrates.

In the Lone Star state, vinegaroons are found primarily in the desserts of West Texas, especially in the Trans-Pecos region, though they’ve also been reported as far north as the Panhandle and in South Texas, according to the Texas A&M Agrilife Extension.

They’re considered relatively benign and non poisonous but, as park staff noted, when threatened, they can spray a mist from scent glands at the base of their tail. The mist contains 85% concentrated acetic acid, also known as vinegar. Oh, and if their giant pincers weren’t a tip off, vinageroons pack a mean pinch.

Park staff urged those lucky enough to happen upon a vinegaroon to take a close look. If it’s a female, it could be carrying hatchlings on it back.

RELATED: Gators and coral snakes and cougars, oh my! 9 dangerous Texas critters you definitely don’t want to mess with


About the Author:

Briana Zamora-Nipper joined the KPRC 2 digital team as a community associate producer in 2019. During her time in H-Town, she's covered everything from fancy Houston homes to tropical storms. Previously, she worked at Austin Monthly Magazine and KAGS TV, where she earned a Regional Edward R. Murrow award for her work as a digital producer.