Many different species of brittle stars are found in small aggregations underneath rocks with a sand interface. Brittle stars have the ability to cast off their arms and easily regenerate new limbs. They are often called serpent stars because their flexible arms can be easily moved, as compared with the more rigid seastars. Little is known of their feeding habits, but they are thought to feed on organic material in the sand. They cannot evert their stomach to feed, as is characteristic of seastars.