Yeah i think it looks like one of those rare parasites you usually don't see in the trade. being that they're imports explains it. I doubt its life threatening.
Whats that website with most of them on it..... Can't think of the name at the moment......
-Andrew
Ps. I was looking and found something kinda funny, google freshwater dwarf shrimp and look to the right

RARE FW DWARF SHRIMP FS!!