Alcyonaria (also known as Octocorallia, as they've 8-fold symmetry) is a subclass of the class Anthozoa within the phylum Cnidaria. It includes the sea fans and sea pens, and the soft corals of the order Alcyonacea. The subclass is divided into a number of orders; those which are extinct are marked with †. Alcyonacea (soft corals) Gorgonacea (sea fans, sea feathers) Helioporacea Pennatulacea (sea pens, sea pansies) Stolonifera Telestacea… (More on Alcyonaria)