Belongs within: Anthozoa.
Contains: Calcaxonia, Holaxonia.
The Octocorallia, octocorals, are a well-defined group of mostly colonial cnidarians with polyps with eight tentacles and eight mesenteries, and often with pinnules on the tentacles (Daly et al. 2007). Past classifications of the octocorals have often recognised a distinction between the Gorgonaria (with a horny or calcareous axial skeleton) and the entirely soft-bodied Alcyonaria but phylogenetic studies have not recovered these groups as separate lineages. The greater number of species with a calcareous skeleton remain included in the clade Calcaxonia but the correlation is not complete (McFadden et al. 2021).
Septodaeum siluricum is a Palaeozoic species that has been recorded from the Ordovician to the Devonian (Nudds & Sepkoski 1993). Fossils consist of assemblages of phosphatised tubes. However, Septodaeum has subsequently been re-identified as a possible bryozoan. Echmatocrinus brachiatus is an irregularly plated, cup-shaped fossil from the Middle Cambrian that was originally identified as an early crinoid (Sprinkle & Moore 1978).
Octocorallia [Coenothecalia]
| i. s.: Echmatocrinus Sprinkle 1973A99, SM78 [Echmatocrinea, Echmatocrinida, Echmatocrinidae]
| `--*E. brachiatus Sprinkle 1973SM78
| PetilavenulaEL11
|--Septodaeum [Septodaearia, Septodaeidae]NS93
| `--S. siluricum Bischoff 1978NS93
`--Alcyonacea [Alcyonaria, Alcyoniidae, Gorgonacea, Gorgonaria, Isides, Scleraxonia]DB07
| i. s.: Pseudogorgia [Pseudogorgiidae]DB07
| `--P. godeffroyiDB07
| Calyptrophora Gray 1866G66
| |--*C. japonica Gray 1866G66
| `--C. wyvilleiH04
| Platycaulos danielsseniH04
| Euplexaura parcicladosH04
| Stenella spinosaH04
| Calypterinus allmaniH04
| Juncea barbadensisH04
| Anthomuricea argenteaH04
| CoralliumPP64 [CoralliidaeDB07]
| `--C. rubrum [incl. Isis nobilis]G20
| Leioptilus fimbriatusC-SC03
| HeteroxeniaH94
| ParerythropodiumH94
| |--P. coralloides [=Alcyonium coralloides]PP64
| `--P. fulvumH94
| Calcigorgia spiculiferaD10
| Acanthoisis flabellumH15
| Pseudoplexaura wagenaariW87
| Pragnellia arborescens Leith 1952NS93
| Militaea ochraceaG20
| Pterogorgia ancepsR22
| Eriska Risso 1826R26
| `--*E. velutina Risso 1826R26
| EleutherobiaMG-H11
| InflatocalyxMG-H11
| Atractosella cataractaca Bengtson 1981NS93
| LobophytumBS14
| |--L. crassum von Marenzeller 1886BS14
| |--L. crebriplicatum von Marenzeller 1886BS14
| |--L. cristagalliH94
| |--L. latilobatumH94
| `--L. pauciflorum Ehrenberg 1833WG71
| Minabea aldersladei Williams 1992BS14
| Dampia pocilloporaeformis Alderslade 1983BS14
|--CalcaxoniaMQ21
`--HolaxoniaMQ21
*Type species of generic name indicated
References
[A99] Ausich, W. I. 1999. Origin of crinoids. In: Candia Carnevali, M. D., & F. Bonasoro (eds) Echinoderm Research 1998 pp. 237–242. A. A. Balkema: Rotterdam.
[BS14] Bryce, M., & A. Sampey. 2014. Kimberley marine biota. Historical data: soft corals and sea fans (Octocorallia). Records of the Western Australian Museum Supplement 84: 101–110.
[C-SC03] Cavalier-Smith, T., & E. E.-Y. Chao. 2003. Phylogeny of Choanozoa, Apusozoa, and other Protozoa and early eukaryote megaevolution. Journal of Molecular Evolution 56: 540–563.
[DB07] Daly, M., M. R. Brugler, P. Cartwright, A. G. Collins, M. N. Dawson, D. G. Fautin, S. C. France, C. S. McFadden, D. M. Opresko, E. Rodriguez, S. L. Romano & J. L. Stake. 2007. The phylum Cnidaria: a review of phylogenetic patterns and diversity 300 years after Linnaeus. Zootaxa 1668: 127–182.
[D10] Dautova, T. N. 2010. Cnidaria diversity in the northwest Pacific: pathways of the dispersal. In: China-Russia Bilateral Symposium: Proceedings of the China-Russia Bilateral Symposium of “Comparison on Marine Biodiversity in the Northwest Pacific Ocean”, 10–11 October 2010, Qingdao (China) pp. 82–87. Institute of Oceanology, Chinese Academy of Sciences; A. V. Zhirmunsky Institute of Marine Biology, Far East Branch of the Russian Academy of Sciences.
[EL11] Erwin, D. H., M. Laflamme, S. M. Tweedt, E. A. Sperling, D. Pisani & K. J. Peterson. 2011. The Cambrian conundrum: early divergence and later ecological success in the early history of animals. Science 334: 1091–1097.
[G20] Goldfuss, G. A. 1820. Handbuch der Naturgeschichte vol. 3. Handbuch der Zoologie pt 1. Johann Leonhard Schrag: Nürnberg.
[G66] Gray, J. E. 1866. Description of two new forms of gorgonioid corals. Proceedings of the Zoological Society of London 1866: 24–27.
[H04] Haeckel, E. 1899–1904. Kunstformen der Natur. Bibliographisches Institut: Leipzig und Wien.
[H15] Hedley, C. 1915. Presidential address. Journal and Proceedings of the Royal Society of New South Wales 49 (1): 1–77, pls 1–7.
[H94] Humes, A. G. 1994. Two species of Paramolgus (Copepoda: Poecilostomatoida: Lichomolgidae) associated with the scleractinian Pavona in New Caledonia with a key to the females of Paramolgus. Beaufortia 44 (1): 1–9.
[MG-H11] McEnnulty, F. R., K. L. Gowlett-Holmes, A. Williams, F. Althaus, J. Fromont, G. C. B. Poore, T. D. O’Hara, L. Marsh, P. Kott, S. Slack-Smith, P. Alderslade & M. V. Kitahara. 2011. The deepwater megabenthic invertebrates on the western continental margin of Australia (100–1100 m depths): composition, distribution and novelty. Records of the Western Australian Museum Supplement 80: 1–191.
[MQ21] McFadden, C. S., A. M. Quattrini, M. R. Brugler, P. F. Cowman, L. F. Dueñas, M. V. Kitahara, D. A. Paz-García, J. D. Reimer & E. Rodríguez. 2021. Phylogenomics, origin, and diversification of anthozoans (phylum Cnidaria). Systematic Biology 70 (4): 635–647.
[NS93] Nudds, J. R., & J. J. Sepkoski Jr. 1993. Coelenterata. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 101–124. Chapman & Hall: London.
[PP64] Peres, J. M., & J. Picard. 1964. Nouveau manuel de bionomie benthique de la mer Mediterranee. Recueil des Travaux de la Station Marine d’Endoume, Bulletin 31 (27): 5–137.
[R26] Risso, A. 1826. Histoire naturelle des principales productions de l’Europe méridionale et particulièrement de celles des environs de Nice et des Alpes maritimes vol. 5. F.-G. Levrault: Paris.
[R22] Runnegar, B. 2022. Following the logic behind biological interpretations of the Ediacaran biotas. Geological Magazine 159 (7): 1093–1117.
[SM78] Sprinkle, J., & R. C. Moore. 1978. Echmatocrinea. In: Moore, R. C., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt T. Echinodermata 2. Crinoidea vol. 2 pp. T405–T407. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).
[WG71] Wilson, B. R., & K. Gillett. 1971. Australian Shells: illustrating and describing 600 species of marine gastropods found in Australian waters. A. H. & A. W. Reed: Sydney.
[W87] Withers, N. 1987. Dinoflagellate sterols. In: Taylor, F. J. R. (ed.) The Biology of Dinoflagellates pp. 316–359. Blackwell Scientific.