Anthozoa

Taxobox
name = Anthozoa |

image_width = 250px
image_caption = Stony corals, "Scleractinia"
regnum = Animalia
phylum = Cnidaria
classis = Anthozoa
classis_authority = Ehrenberg, 1831

Anthozoa is a class within the phylum Cnidaria that contains the sea anemones and corals. Unlike other cnidarians, anthozoans do not have a medusa stage in their development. Instead, they release sperm and eggs that form a planula, which attaches to some substrate on which the cnidarian grows. Some anthozoans can also reproduce asexually through budding.

All cnidarian species can feed by catching prey with nematocysts, sea anemones capable of catching fish and corals catching plankton. Some of the species also harbour a type of algae, dinoflagellates called zooxanthellae, in a symbiotic relationship; the reef building corals known as hermatypic corals rely on this symbiotic relationship particularly. The zooxanthellae benefit by using nitrogenous waste and carbon dioxide produced by the host, and the cnidarian gains photosynthetic capability and increased calcium carbonate production in hermatypic corals. [http://www.sbg.ac.at/ipk/avstudio/pierofun/png/png3.htm Contribution to the BUFUS Newsletter, Field excursion to Milne Bay Province - Papua New Guinea, Madl and Yip 2000] ]

Anemones and certain species of coral live in isolation, however most corals form colonies of genetically identical polyps; these polyps closely resemble anemonies in structure, although are generally considerably smaller. Most kinds of stony coral live in all parts of the underwater world.

[
Giant green anemone, likely Epicystis crucifer, Southern California]

Phylogeny

The two subclasses are divided into a number of orderscite web
author = Fautin, Daphne G. and Romano, Sandra L.
year = 2000
url = http://tolweb.org/Anthozoa/17634/2000.10.03
title = Anthozoa. Sea Anemones, Corals, Sea Pens.
format =
work = The Tree of Life Web Project
publisher =
accessdate = 2006-03-31] and a series of orders.cite journal
author = Chen, C. A., D. M. Odorico, M. ten Lohuis, J. E. N. Veron, and D. J. Miller
year = 1995
month = June
title = Systematic relationships within the Anthozoa (Cnidaria: Anthozoa) using the 5'-end of the 28S rDNA
journal = Molecular Phylogeny and Evolution
volume = 4
issue = 2
pages = 175–183
pmid = 7663762
url = http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6WNH-45R889V-14-1&_cdi=6963&_user=10&_orig=search&_coverDate=06%2F30%2F1995&_qd=1&_sk=999959997&view=c&wchp=dGLbVzz-zSkzV&md5=531282d4acffe5b53431d2dcb91df8a8&ie=/sdarticle.pdf
doi = 10.1006/mpev.1995.1017] cite journal
author = France, S. C., P. E. Rosel, J. E. Agenbroad, L. S. Mullineaux, and T. D. Kocher
year = 1996
month = March
title = DNA sequence variation of mitochondrial large-subunit rRNA provides support for a two subclass organization of the Anthozoa (Cnidaria)
journal = Molecular Marine Biology and Biotechnology
volume = 5
issue = 1
pages = 15–28
pmid = 8869515
url = ] cite web
author = Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey
year = 2006
url = http://tolweb.org/Anthozoa/17634/2000.10.03
title = Subclass Alcyonaria
work = The Animal Diversity Web (online)
accessdate = 2006-03-31] cite web
author = Ben Kotrc
year = 2005
url = http://palaeo.gly.bris.ac.uk/Palaeofiles/Fossilgroups/anthozoa/subgroups.html
title = Anthozoa: Subgroups
format =
work = Fossil Groups
publisher = University of Bristol
accessdate = 2007-04-09] , extinct orders from the Paleozoic (570-245 m.y.a.)cite book
author = Oliver, W. A., Jr.
editor = G. D. J. Stanley (ed.)
year = 1996
title = Paleobiology and Biology of Corals
chapter = Origins and relationships of Paleozoic coral groups and the origin of the Scleractinia
pages = 107-134
publisher = The Paleontological Society
location = Columbus, Ohio] are marked with †.
*Subclass Alcyonaria (= Octocorallia) (8-way symmetry)
**Alcyonacea (soft corals)
**Gorgonacea (sea fans, sea feathers)
**Helioporacea (= Coenothecalia) (Indo-Pacific blue coral)
**Pennatulacea (sea pens, sea pansies)
**Stolonifera (organ-pipe coral, tree fern coral)
**Telestacea (soft corals)
*Subclass Zoantharia (= Hexacorallia) (6-way symmetry)
**Ceriantharia (tube-dwelling anemones)
**Actiniaria (sea anemones)
**Corallimorpharia
**Numidiaphyllida †
**Scleractinia (= Madreporaria) (stony corals)
**Kilbuchophyllida †
**Antipatharia (black corals, thorny corals)
**Zoanthidea
**Heterocorallia †
**Rugosa † (= Tetracoralla) (horned corals)
**Heliolitida †
**Tabulata † (tabulate corals)
**Cothoniida †
**Tabuloconida †
**Ptychodactiaria

References