Small reddish insect that bites?

I'm hitting the books and doing some research, but I figured I'd see what anyone here could give me in the meantime. My sister just called to describe an insect. She said it was a little smaller than an ant, red (not lady beetle red but a darkish red), six legs, long antennae in comparison to its body length, no wings (or none that she noticed) and it gave her a painful bite. I'm thinking it may have been a nymph, whatever it was, but I'm not sure. Let me know if you know what it could be.