CLASSIFICATION OF GORGONIA
PHYLUM :- COELENTRATA OR CNIDARIA (Tissue grade, diploblastic and acoelomate. )
CLASS :- ANTHOZOA OR ACTINOZOA (Only polypoid generation. sedentary, solitary, colonial.)
SUB-CLASS :- OCTOCORALLIA (Polyps with 8 tentacles, bioluminescent.)
ORDER :- GORGONACEA (Horny corals, polyps short not reaching up to base.)
SUB-ORDER :- SCLERAXONIA (With axial spicule)
FAMILY :-GORGONIDA (Slender stem, thin, coenenchyme and partially retractile anthocodia. )
GENUS :- Gorgonia (Sea fan)
Found in South Atlantic and West Indies, Indo-Pacific ocean, Malay Archipelago, Bermuda and Bahamas.
HABIT AND HABITAT
Gorgonia is a colonial form inhabiting all seas from tide mark to over 4000 meters. Most of them are littoral. Some prefer warmer seas. Shallow water forms have fan-like structure. Deep sea fonns branch in all directions. It fonns one of the chief attractions of the submarine gardens of shallow tropical and subtropical waters
GENERAL CHARACTERSTICS OF GORGONIA
- Commonly called as Sea fan, whose graceful form and soft colouration constitute one of the chief attractions of ‘submarine’ gardens.
- It forms erect, yellowish or reddish arborescent branches in one plane connected by cross connections in a feathery manner and contour of the body becomes fan-like
- Branches are united by numerous cross-branches, foming a network with meshes 2 to 5 mm wide, calcareous in nature.
- Base of the colony is expanded to form a hold fast organ called as pedal disk.
- Polyps or anthocodia emerge from branches and contain 8 pinnate tentacles, mouth, gastrovascular cavity, 8 gastric filaments and mesenteries.
- Polyps occur in rows and on two sides only of the stem and its branches. In magnified portions holes for polyps are seen.
- Skeleton consists of hornlike material called Gorgonin embedded in mesogloea. An axial rod extended throughout the colony and its branches. Axial rod consists of medulla and cortex. Gorgonin is proteinaceous consisting of tyrosine amino-acid.
- Sexes are separate.
Gorgonia is very familiar museum specimen due to its fan-shaped body. The dried skeleton is often displayed as ornament. Sea fan has power of regeneration. It can form new anthocodia when branches are broken off. The heavy harm caused to gorgonian bed by storm is repaired.
The animal contains fan shaped body and all above characters and hence it is Gorgonia.