Gorgonin

Gorgonin , also called pennatulin , is a horn-like scleroprotein with a low sulfur content. It resembles the organic skeletal substance of black corals (Antipatharia). It is excreted by some groups of Octocorallia in order to build up or stabilize the skeleton.

Gorgonin as part of the skeleton

In addition to the free calcareous sclerites in the coenenchyma , some octocorallia also have axial structures, which they basically produce in one of the two following ways.

In species of the suborder Scleraxonia , sclerites are united by gorgonine and / or calcium deposits in different steps and form a medulla.

In other taxa of the suborder Holaxonia , the axis consists of a horny central rod (Gorgonin), which is often calcified and sometimes detached in calcareous sections. The former process creates a vital internal structure (it is a product of the cells of the coenenchyma) that is often heavily penetrated by thin channels called solenia . The second method creates a comparable but not identical structure that is deposited outside the coenenchyme and is never penetrated by solenia.

One family, the Keroeididae , contains single- axis species that have characteristics of both of these methods of skeletal formation. The species have a proteinaceous (holaxonal) medulla in the center. The medulla is embedded by sclerites, which are embedded in a gorgonin layer according to the scleraxonal method.

literature

• Bernhard Werner: Cnidaria tribe. In: Textbook of Special Zoology. Volume I: Invertebrates Part 2 : Cnidaria, Ctenophora, Mesozoa, Plathelminthes, Nemertini, Entoprocta, Nemathelminthes, Priapulida. 4th, completely revised edition. Gustav Fischer Verlag, Stuttgart 1984, ISBN 3-437-20261-8 , pp. 11-305.