A starfish, one of the dumbest creatures under the sea, but everyone loves him anyway. He lives 2 houses away from SpongeBob, under a rock that opens by a hinge. His hobbies include going jellyfishing and getting into trouble along with Spongebob.
Starfish or sea stars are echinoderms belonging to the class Asteroidea. The names "starfish" and "sea star" essentially refer to members of the Class Asteroidea. However, common usage frequently finds "starfish" and "sea star" also applied to ophiuroids which are correctly referred to as "brittle stars" or "basket stars". Starfish are among the most familiar of marine animals and possess a number of widely known traits, such as regeneration and feeding on mussels. Starfish possess a wide diversity of body forms and feeding methods. The extent that Asteroidea can regenerate varies with individual species. Broadly speaking, starfish are opportunistic feeders, with several species having specialized feeding behavior, including suspension feeding and specialized predation on specific prey.
The life cycle of a star fish are capable of both sexual and asexual reproduction. Most species are dioecious, with separate male and female individuals, but some are hermaphrodites. Male and female sea stars are not distinguishable from the outside; one needs to see the gonads or be lucky enough to catch them spawning. Each arm contains two gonads, which release gametes through openings called gonoducts, located on the central body between the arms.
The lifespan of starfish varies considerably between species, generally being longer in larger species. For example, Leptasterias hexactis (adult weight 2 grams) reaches sexual maturity in two years, and lives for about ten years in total, while Pisaster ochraceus (adult weight 80 grams) reaches maturity in five years, and may live to the age of 34.
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