Formerly known as Starfish, these Echinoderms are found intertidally to the deep ocean floor. They are omnivores, hunters and scavengers and have been known to exhibit aggressive behavior towards each other. They are strictly marine - not found in freshwater or on land. There are about 1,500 species of seastars, all having arms radiating from a central disk. At the end of each arm is an eyespot, which cannot focus like a real eye but is sensitive to darkness and light. The perforated buttonlike sieve plate found on the aboral (dorsal/top) surface is the opening to the seastar's water vascular system of canals. These canals extend into each stout arm of the seastar, helping to work that arm's tiny tubed feet found on the seastar's oral (ventral/bottom) surface. They often evert their stomachs to feed. Their stomachs exit their bodies and enter through the cracks in shells of bivalves. They then send out digestive enzymes. Many species have tiny pincers on the aboral surface, which keeps the seastars clean.
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Bat Stars |
Blood Stars |
Giant Spined |
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Leather Star |
Rainbow Star |
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