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
Starfish from bilateral organisms, starfish move in a bilateral fashion, with certain arms acting like the front of the animal. The body wall consists of a thin cuticle, an epidermis consisting of a single layer of cells, a thick dermis formed of connective tissue and a thin coelomic myoepithelial layer, which provides the longitudinal and circular musculature. The dermis contains an endoskeleton of calcium carbonate components known as ossicles. These are honeycombed structures composed of calcite microcrystals arranged in a lattice. They vary in form, with some bearing external granules, tubercles and spines, but most are tabular plates that fit neatly