(The guy's English was great so this is an unfair sentence to pick out but that's what he said.)
What Luis knows familiarly as a chincha, I can only identify, clinically, as a coreid, or leaf-footed bug, member of the class of "true bugs" or hemipterans, etc. You would sort of know one of these if you saw it but unless you were an entomologist you wouldn't have a ready name for it. Luis just looked at these pearly blisters and said, "Ah, chincha." Since noticing them I had been entertaining everything from splashed coffee to leprosy.
Here's a different variety of chincha that we found later that morning in the jungle:
Lie down with chinchas, wake up with little blisters.
Here is a cool picture of a tree that was clawed by a jaguar:
