; class Anthozoa, subclass Octocorallia)
An order of colonial octocorals that are anchored by a holdfast and have a tree-like shape supported by a branching, central skeleton of horn-like, organic material (gorgonin) or calcareous material, or both. They first appeared in the Cretaceous. The order contains two suborders, 18 families, and about 120 genera.
Subjects: Zoology and Animal Sciences.