Palaeos:		Anthozoa
Cnidaria		Octocorallia

In this group of mostly soft corals, the polyps are almost always formed into colonies, each polyp having eight pinnate (side- branching) tentacles. Octocorallians include a number of diverse forms

Alcyonacea - sometimes known as 'soft corals'. Often inhabit low tidal zone of rocky shores

Gorgonacea - members secrete a horny material called gorgonin to act as skeletal support. Abundant on coral reefs, especially in the Caribbean.

<==o ALCYONARIA
   |--o PROTOALCYONARIA
   |  |-- Haimeidae
   |  `-- Taiaroidae
   |--o STOLONIFERA
   |  |-- Clavulariidae
   |  |-- Cornulariidae
   |  `-- Tubiporidae
   |--o TELESTACEA
   |  |-- Coelogorgiidae
   |  |-- Pseudocladochonidae
   |  `-- Telestidae
   |--o GASTRAXONACEA
   |  `-- Pseudogorgiidae*
   |--o GORGONACEA
   |  |--o HOLAXONIA
   |  |  |-- Acanthogorgiidae
   |  |  |-- Ainigmaptilidae
   |  |  |-- Chrysogorgiidae
   |  |  |-- Ellisellidae
   |  |  |-- Gorgoniidae
   |  |  |-- Ifalukellidae
   |  |  |-- Isididae
   |  |  |-- Keroeididae
   |  |  |-- Paramuriceidae
   |  |  |-- Plexauridae
   |  |  `-- Primnoidae
   |  `--o SCLERAXONIA
   |     |-- Anthothelidae
   |     |-- Briareidae
   |     |-- Coralliidae
   |     |-- Melithaeidae
   |     |-- Paragorgiidae
   |     |-- Parisididae
   |     `-- Subergorgiidae
   |--o ALCYONACEA
   |  |-- Alcyoniidae
   |  |-- Astrospiculariidae
   |  |-- Maasellidae
   |  |-- Nephtheidae
   |  |-- Siphonogorgiidae
   |  `-- Xeniidae
   |?- PENNATULACEA (merisulat)
   `--o HELIOPORACEA
      |-- Helioporidae
      `-- Lithotelestidae

Pennatulacea - the sea pens, have a single long main polyp forms a stalk which anchors the colony in its mud substrate. Branches from this bear the feeding and ciliated polyps and generate an inward current of water that keeps the whole colony inflated.  It used to be thought that some Edicarian forms were sea-pens, this does not seem to be the case.

See also Race Rocks - Ptilosarcus gurneyi - for more on the Sea Pens.

<==o PENNATULACEA 
   |--o SESSILIFLORAE
   |  |-- Anthoptilidae
   |  |-- Chunellidae
   |  |-- Echinoptilidae
   |  |-- Funiculinidae
   |  |-- Kophobelemnidae
   |  |-- Protoptilidae
   |  |-- Renillidae
   |  |-- Scleroptilidae
   |  |-- Stachyptilidae
   |  |-- Umbellulidae
   |  `-- Veretillidae
   `--o SUBSELLIFLORAE
      |-- Pennatulidae
      |-- Pteroeididae
      `-- Virgulariidae