ABSTRACT
Coral reefs are generally comprised of a complex array of communities that may include many different types of coelenterates such as cnidarians (which include hard or stony corals, soft corals, sea whips and sea fans, sea pens, hydroids, zoanthids, and sea anemones) as well as ascidians (tunicates) and sponges. The corals are comprised of hexacorals (stony corals), where polyps have six or multiples of six tentacles, and octocorals, where polyps have eight tentacles. These sedentary coelenterates are generally not restricted to tropical coral reefs, and species are also found in subtropical, temperate, Arctic, and Antarctic waters.
