Pea crab

Pinnotheres is Greek for "guard of Pinna" and pisum is Latin for a pea, in reference to the shape of the crab. ==Description==

Pea crabs are small crustaceans about the size of a pea or dime, with a "smooth dorsal surface of the carapace, or upper exoskeleton". The exoskeleton of males is hard and circular and has eyes and antennae extending from their fronts, and the chelipeds are more robust in males than in females, which have more elongated chelipeds. The bodies of the female pea crabs are often translucent and show the inner organs and gonads as yellow and red, with the males being a "more yellowish-grey with patches of brown". ==Ecology==

The relationship between the pea crab and its host is one of parasitism, rather than commensalism, since the host may be harmed by the crab's feeding activities. The pea crab relies solely on its host for food, safety, and oxygen. Pea crabs have a variety of hosts, the most important of which are molluscs. The pea crab lives in the mantle cavity of these hosts. The feeding process can be harmful to the crab's host when it feeds on the mucous strings that help carry the food to the host's mouth. , California) == Mating ==

shows this behaviour in a similar parasitic pea crab, Nepinnotheres novaezelandiae. == See also ==