Starfish or sea stars are echinoderms belonging to the class Asteroidea. The names "starfish" and "sea star" essentially refer to members of this class.Starfish
are among the most familiar of marine invertebrates. They typically
have a central disc and five arms, though some species have more than
this. The aboral or upper surface may be smooth, granular or spiny, and
is covered with overlapping plates. Many species are brightly coloured
in various shades of red or orange, while others are blue, grey or
brown. Starfish have tube feet operated by a hydraulic system and a mouth at the centre of the oral or lower surface. They are opportunistic feeders and are mostly predators. They have complex life cycles and can reproduce both sexually and asexually. Most can regenerate damaged parts or lost arms and they can shed arms as a means of defence. While a starfish lacks a centralized brain, it has a complex nervous system.
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| Huge starfish on Case inlet beach - LINK |
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| Vancouver
Island, British Columbia, Canada - LINK |
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| Starfish at Budleigh Salterton. Photo credit: Scott Eley - LINK |
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