CLASSIFICATION OF CLIONA
PHYLUM :- PORIFERA (Pore bearing, cellular grade, asymmetrical or radially symmetrical.)
CLASS :- DEMOSPONGIAE (Skeleton of spongin fibres or siliceous spicules which are not six-rayed.)
ORDER :- Monaxonida (Spongin mayor may not be present; spicules monaxon.)
GENUS :- Cliona
Cosmopolitan, very common in South Carolina.
HABIT AND HABITAT
Cliona forms low encrustation on rocks, coral skeletons, mollusc shells and other calcareous objects.
GENERAL CHARACTERSTICS OF CLIONA
- Commonly called as boring sponge .
- It is a light yellow coloured sponge.
- Sponge forms a mass up to approximately 20 cm in diameter.
- Proximal end or base is attached to substratum.
- Clam shell, specially Venus, is completely riddled by it.
- It enters the interior of above animals and lives permanently there, forming extensive burrows and tunnels.
- Each tunnel has a raised opening, called osculum.
- The surface shows various elevations each containing an osculum and large number of coral cups.
- Reproduction sexual and early stages-free-living. The larva grows into a compact mass, 17 to 70 cm in diameter made up of spongin fibres and monaxial siliceous spicules.
- Various oscula are seen over the surface.
The sponge beings its existence by boring in the dead or living shells of various molluscs. It honeycombs the shell and after destroying it grows over it. Cliona celata has sulphurous odour.
The animal has raised oscula, pores and coral cups and all above features hence it is Cliona.