ID this bug

[BasementJungle]

My friends found 2 of these, dead, on the shore of a small stream in Pennsylvania. Maybe a predatory beetle nymph?

http://community.webshots.com/photo/409464966/2545081710075195083bhuzmS#

 

[bugmankeith]

Could be a mayfly larvae, it looks like you found the shed skin.

 

[Gigas]

or they were in mid moult when you or your friends found em, i agree with mayfly

 

[Dark Raptor]

It looks like Plecoptera exuvium.