(class Anthozoa, subclass Octocorallia)
An order of colonial corals which first appeared in the Cretaceous and which includes the modern genus Heliopora (blue coral) common in tropical Pacific reefs. Members are characterized by a massive skeleton of fibrocrystalline aragonite, the skeleton being perforated by wide tubes which house the polyps, and by narrow tubes containing blind downgrowths of solenial tissue (see solenium). The order contains two families, and three genera.
Subjects: Zoology and Animal Sciences.