I saw some for sale in Super Pet the other day and my boyfriend freaked out because he didn't think they were even legal! I mean, the things can survive OUT OF WATER!!! That's flipping crazy! *shudders*
Honestly, I have no idea, but I don't think it was a parasitic one. Next time I go to Super Pet I'll take a closer look, but I remember reading that it grew to be pretty **** long.