starfish
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”.
About 1,800 living species of starfish occur in all the world’s oceans, including the Atlantic, Pacific, Indian, Arctic and Southern Oceansregions. Starfish occur across a broad depth range from the intertidal to abyssal depths (>6000 m).
Starfish are among the most familiar of marine animals and possess a number of widely known characteristics, such as regeneration and feeding on mussels. They possess a wide diversity of body forms and feeding methods. The extent to which Asteroidea can regenerate varies with individual species. Broadly speaking, starfish are opportunistic feeders, with several species having specialized feeding behaviors, including suspension feeding and specialized predation on specific prey.
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