Unnamed spotting

Habitat:

Rock wall

Notes:

I found this small arthropod stuck to a stone wall in a campground in Kentucky. It was about 1/8th of an inch long and stuck tight to the wall. I couldn't pry it off without injuring it. All the legs appeared to be near the head of the creature. I don't know how many legs it had; it was hard to count them with the "thorns" adorning them. I'm curious as to what it is.