Alcyonacea is an
order of
sessile colonial cnidarians found throughout the oceans of the world, especially in the
tropics and
subtropics. The name "Gorgonacea" is no longer considered valid and
Alcyonacea is now the accepted name for the order. Gorgonians are also known as
sea whips and
sea fans and are similar to the
sea pen, a soft coral. Gorgonians are closely related to
coral. Individual tiny
polyps form colonies that are normally erect, flattened, branching, and reminiscent of a
fan. Others may be whiplike, bushy, or even encrusting. A colony can be several feet high and across but only a few inches thick. They may be brightly coloured, often purple, red, or yellow. Photosynthetic gorgonians can be successfully kept in captive
reef aquariums.
