Crown-of-thorns starfish occurs where coral reefs or hard coral communities occur in this region. The body form of the crown-of-thorns starfish is fundamentally the same as that of a typical starfish, with a central disk and radiating arms. Its special traits, however, include being disc-shaped, multiple-armed, flexible, prehensile, and heavily spined, and having a large ratio of stomach surface to body mass. Its prehensile ability arises from the two rows of numerous tube feet that extend to the tip of each arm. In being multiple-armed, it has lost the five-fold symmetry (pentamerism) typical of starfish, although it begins its life cycle with
Reef starfish Reef starfish Reef starfish (Stichaster australis) is a species of starfish found in the South Pacific Ocean around New Zealand. A keystone species, the carnivorous starfish plays an important part in reducing the expansion of mussels. "S. australis" is pink or purple in color, with 11 arms. Found throughout New Zealand, "S. australis" is a keystone species in both the North and South Islands, playing an important role in mussel predation. In one study on the west coast of the South Island conducted in the 1970s, "S. australis" was found to have removed a majority of transplanted mussels within two