Every Alcyonarian FIG.
- Transverse section of an colony is developed by Alcyonarian zooid.
- An expanded Alcyonarian zooid, showing the mouth surrounded by eight pinnate tentacles.
Formerly all corals in which tabulae are present were classed together as Tabulata, but Tubipora is an undoubted Alcyonarian with a lamellar stolon, and the structure of the fossil genus Syringopora, which has vertical corallites united by horizontal solenia, clearly shows its affinity to Tubipora.
The structure of the zooid of Heliopora, however, is that of a typical Alcyonarian, and the septa have only a resemblance to, but no real homology with, the similarly named structures in madreporarian corals.