Researchers have discovered a new half-scorpion, half-spider animal lurking in the dark caves of Yosemite National Park, according to Texas Tech University News.

The creature is a type of pseudoscorpion, tiny arachnids that have abdomens like spiders with eight spidery legs and claws like scorpions. Unlike real scorpions, these creatures lack a long post-abdomen stinger. Normally that would be good news, but this new species makes up for it with the addition of venom-filled claws.

Luckily the new pseudoscorpion (Parobisium yosemite) is also blind, slow-moving and very small, typically measuring no longer than about half an inch. So there's no reason to jump to cancel those summer vacation plans to Yosemite just yet.

The animal is also only found deep in dark granite caves, one of the main reasons the discovery took so long.

"The canyon where it was found was made by a glacier during an ice age millions of years ago," noted James Cokendolpher, one of the researchers who documented the find. "Through time, rubble with larger rocks would fall and create piles with caves or subterranean voids. We think that’s where this animal was trapped and evolved into the species that it is now."

Cokendolpher also said that finding the pseudoscorpion in granite caves was particularly unusual because most cave-dwelling species live in limestone caves, where better humidity and access to food makes the environment more hospitable. The new species is probably only the second pseudoscorpion ever found in a granite enclosure.

Even though they are harmless to humans, the way these tiny predatory arachnids hunt is eerie nonetheless.

"We kept them in petri dishes with plaster of Paris that was moistened so it was more like cave conditions," Cokendolpher explained to the [skipwords]Texas[/skipwords] Tech University News. "When we introduced other animals into the petri dish it would go over and tap the animal [with its venom-filled claws]. When it did that, it was able to sense chemical cues there such as identification, how large the item was and whether it was something suitable to eat."

At the very least, it's enough to make even seasoned spelunkers think twice about any tap-tap they might encounter while exploring in the dark.

Watch a full interview with researcher Cokendolpher about the new pseudoscorpions here:

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