<P> 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 , 6,000 m ( 20,000 ft ) below the surface . </P>
<P> 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 , 6,000 m ( 20,000 ft ) below the surface . </P>
how many species of sea stars are there
how many species of sea stars are there
About 1,500
About 1,500