cover image

Hexacorallia

Class of cnidarians with 6-fold symmetry / From Wikipedia, the free encyclopedia

Hexacorallia is a class of Anthozoa comprising approximately 4,300 species of aquatic organisms formed of polyps, generally with 6-fold symmetry. It includes all of the stony corals, most of which are colonial and reef-forming, as well as all sea anemones, and zoanthids, arranged within five extant orders.[2] The hexacorallia are distinguished from another class of Anthozoa, Octocorallia, in having six or fewer axes of symmetry in their body structure; the tentacles are simple and unbranched and normally number more than eight.[3] These organisms are formed of individual soft polyps which in some species live in colonies and can secrete a calcite skeleton. As with all Cnidarians, these organisms have a complex life cycle including a motile planktonic phase and a later characteristic sessile phase. Hexacorallia also include the significant extinct order of rugose corals.

Quick facts: Hexacorallia Temporal range Fortunian–Presen...
Hexacorallia
Temporal range: Fortunian–Present[1]
Acropora_latistella_%28Table_coral%29.jpg
A stony coral, Acropora latistella
Scientific classification e
Kingdom: Animalia
Phylum: Cnidaria
Subphylum: Anthozoa
Class: Hexacorallia
Orders

See text.

Close
Aspidiscus_top.jpg
Aspidiscus cristatus from the Cenomanian (Upper Cretaceous) of southern Israel; oral view.
Aspidiscus_reverse.jpg
Aspidiscus cristatus from the Cenomanian (Upper Cretaceous) of southern Israel; aboral view.