SEA STAR, sometimes called starfish, is a bottom-dwelling marine animal of the phylum Echinodermata. Most species have 5 arms (rays) arranged symmetrically around a central disk, or body. Some have 6 arms or more, but begin life with 5. The sunflower star (Pycnopodia helianthoides), BC's largest, measuring up to 1 m across, has anywhere from 15 to 24 rays. The sea star is an echinoderm; that is, it has an internal skeleton, radial symmetry and a vascular system in which water pressure is used...
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