Arachnophobes, this story isn't for you.
Scientist Piotr Naskrecki posted photos from a recent trip to a rainforest in Guyana, where he stumbled upon a hairy, brown spider the size of a puppy.
Recommended Videos
He heard rustling underfoot and expected to see a small mammal.
"When I turned on the light, I couldn't quite understand what I was seeing," Naskrecki, an entomologist and photographer at Harvard University's Museum of Comparative Zoology, told LiveScience.
What he found was a South American Goliath birdeater -- which, it turns out, is the world's largest spider.
29238848
Sporting two-inch fangs and a body the size of a large fist, the spider may look imposing, but is no big threat to humans, Naskrecki wrote in his blog.
Its bite is venomous, but not deadly.
But you should still beware.
When Naskrecki approached the creature, it began rubbing its hind legs against its abdomen. The action sent out a cloud of hairs with microscopic barbs on them that can be "extremely painful" if they get in your eyes or nose, he said.
Check out more images of the spider on Naskrecki's blog here.