Starfish Starfish Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or "basket stars". About 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters. They are found from the intertidal zone down to abyssal depths, below the surface. Starfish are marine invertebrates. They typically have a central disc and five arms, though some species have a larger number of arms. The aboral or upper surface may be smooth,
Asexual reproduction in starfish generate new individuals in this way. He thought the arms might be shed by autotomy. In the same year, Monks showed experimentally that the "comets" developing from the severed arms of "Linckia columbiae" could indeed grow into new individuals. "Linckia multifora" and "Linckia guildingi" are two species of starfish found on Hawaii which were found to exhibit autotomy, shedding one or more arms frequently. The arms are known as "comets" and can move about independently and each one can grow into a new individual. Though severed from the nervous system and the water vascular system they still exhibit normal behaviour