The decapod crustacean, such as a crab, lobster, shrimp or prawn,'s made up of nineteen body segments grouped into two main body parts, the cephalothorax and the abdomen. Each segment may possess one pair of appendages, although in various groups these may be reduced or missing. They're, from head to tail: Cephalothorax Head antennules antennae mandibles first maxillae second maxillae The head also bears the (usually stalked) compound eyes. Thorax / Pereon first maxillipeds second maxil… (More on Pleopod)