The Vinegaroon Sprays Acid to Foil Its Foes
The vinegaroon – also known as a whip scorpion – looks like a Frankenstein creation of monster body parts. But unlike true scorpions, it doesn’t use venom to defend itself from predators. Instead, it aims its tail at their face and sprays a blast of acid that reeks of – you guessed it – vinegar. Only this weaponized vinegar is 16 times stronger than what’s in your salad.
Late at night, after a rain in Arizona’s high desert, a dark shape creeps out from its underground lair. It’s as big as your palm, and it’s hungry. And if it feels bothered …
OK, what just happened?? And seriously, what is this thing? A mutant land lobster?
I mean, it’s got claws like a scorpion. The mouth of a spider?
Antennae-like things coming out of its armpits.
A long, skinny tail like a ... RAT?
This surprising combo of monster body parts is a vinegaroon, also known as a whip scorpion. It’s in a group of animals called arachnids, that includes scorpions and spiders.
But it doesn’t sting like a scorpion, or hunt with a web like many spiders. A vinegaroon has its very own style.
This tail may look dangerous, but it’s actually a finely tuned sensor. It picks up vibrations and chemicals in the air, in this case, to stalk its prey.
Up front, those antennae-looking things are actually specialized legs. They help the vinegaroon feel its way around. It’s basically blind. So it relies on touch and smell to close in on its meal. It will break through this cricket's tough exoskeleton with its claws and bristly mouth.
The vinegaroon also uses these wicked claws to excavate its burrow. Adults and their young use the burrows for protection from predators, and to stay out of the scorching desert sun.
Vinegaroons and their ancestors have survived this way for hundreds of millions of years. So, what does it need that spray for? Researchers observe it by gently holding the animal with forceps.
Despite those frightening looks, this surprising spritz is actually its strongest defense against anything that wants to eat them – like skunks, raccoons or coyotes. Even with poor eyesight, the vinegaroon sprays with incredible accuracy.
Inside, two pygidial glands, also known as “stink glands,” hold the foul fluid. The base of the tail is extremely flexible, and can aim the blast in any direction.
The instant it sprays, the gland openings appear as two retractable nozzles. An adult vinegaroon can shoot up to five times before it needs to let its stink glands fill up again.
The spray reeks. That’s because the solution is mostly acetic acid, the same stuff in the vinegar in your salad dressing, except this cocktail is 16 times stronger. A blast of that to the face of a larger predator is like pepper spray.
While the vinegaroon’s signature defense is unlikely to do any lasting damage, it will certainly leave a lasting impression.