Editing Coral (section)

===Soft corals===
{{see also|Octocorallia}} 
Soft corals have no solid exoskeleton as such. However, their tissues are often reinforced by small supportive elements known as [[sclerites]] made of calcium carbonate. The polyps of soft corals have eight-fold symmetry, which is reflected in the ''Octo'' in Octocorallia.<ref>{{cite journal|doi=10.1017/jpa.2017.49|title=A problematic cnidarian (Cambroctoconus; Octocorallia?) from the Cambrian (Series 2–3) of Laurentia |year=2017 |last1=Peel |first1=John S. |journal=Journal of Paleontology |volume=91 |issue=5 |pages=871–882 |bibcode=2017JPal...91..871P |s2cid=134826884 |doi-access=free }}</ref>

Soft corals vary considerably in form, and most are colonial. A few soft corals are [[stolon]]ate, but the polyps of most are connected by sheets of tissue called coenosarc, and in some species these sheets are thick and the polyps deeply embedded in them. Some soft corals encrust other sea objects or form lobes. Others are tree-like or whip-like and have a central axial skeleton embedded at their base in the matrix of the supporting branch.<ref>{{cite web|url=https://coralreef.noaa.gov/aboutcorals/coral101/anatomy/|title=existing and potential value of coral ecosystems with respect to income and other economic values|last=Administration|first=US Department of Commerce, National Oceanic and Atmospheric|website=coralreef.noaa.gov|language=EN-US|access-date=2018-02-04|url-status=dead|archive-date=2018-02-05|archive-url=https://web.archive.org/web/20180205184335/https://coralreef.noaa.gov/aboutcorals/coral101/anatomy/}}</ref> These branches are composed of a fibrous protein called [[gorgonin]] or of a calcified material.