Starfish belong to the class of Asteroides. Sometimes called sea stars they usually have five or more arms which resemble a star. Not a fish but a member of the echinoderm family they have their skeleton on the outside. Starfish eat by hunting down and capturing shellfish such as clams and oysters and then engulfing them with their stomach. If a starfish loses an arm it is able to grow a new one. Sometimes when you find a starfish on the beach you will see a nub sticking out where there once was an arm. This nub will become a new arm if given enough time.