Green egg crab

This toxic crab is found in Japan from Chiba Prefecture southwards. The crab contains a tetrodotoxin similar to the toxin in fugu (pufferfish) or the toxin in certain mollusks that can induce paralytic shellfish poisoning. The toxin is synthesized by bacteria living symbiotically within the crab. In Okinawa, it is found in the intertidal zone, and because its toxin can be deadly to humans it must be handled with caution.