The Decapoda or decapods (from Ancient Greek δεκάς (dekás), meaning "ten", and πούς (poús), meaning "foot") is a large order of crustaceans within the class Malacostraca, and includes crabs, lobsters, crayfish, shrimp, and prawns. Most decapods are scavengers. The order is estimated to contain nearly 15,000 extant species in around 2,700 genera,...