Stichodactyla gigantea

Stichodactyla gigantea (commonly known as Giant Carpet Anemone)

Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Anthozoa
Order:	Actiniaria
Family:	Stichodactylidae
Genus:	Stichodactyla
Species:	S. gigantea
Binomial name
Stichodactyla gigantea (Forskål, 1775)[1]

Where seen?

This enormous colourful carpet anemone with short skinny tentacles is commonly seen on our Southern shores, usually on hard surfaces such as coral rubble, near reefs. It is also sometimes seen on coral rubble on our Northern shores.

Features:

Those seen about 40-50cm in diameter when exposed out of water. The oral disk expands when submerged. The large oral disk covered with short tentacles so that it resembles a shaggy carpet. The oral disk is often folded and rarely held flat against the surface, unlike Merten's carpet anemone (Stichodactyla mertensii). The long body column is usually buried or inserted into a crevice and ends in a pedal disk that anchors the animal.

Body column is sometimes colourful (bright pink, orange, yellow). Bumps (verrucae) appear as rows of spots, generally in bright colours (pink, purple). They are non-adhesive and found on the upper part of the body column.

Tentacles short (about 1cm), narrow and uniform in length. Usually brown or purplish with lighter coloured tips. The tentacles are not very tightly packed and when submerged, are usually in constant motion. The tentacles are very sticky. It does not have a fringe of long-short tentacles at the edge of the oral disk like Haddon's carpet anemone (Stichodactyla haddoni).

Carpet food:

Carpet anemones harbour symbiotic single-celled algae (called zooxanthallae). The algae undergo photosynthesis to produce food from sunlight. The food produced is shared with the sea anemone, which in return provides the algae with shelter and minerals. The zooxanthallae are believed to give tentacles their brown or greenish tinge. Carpet anemones may also feed on fine particles that are trapped on their bodies. These anemones have not been observed to eat large animals.

Stinging carpet!

Like other sea anemones, the Carpet anemone has stingers in its tentacles. Generally, these stings do not hurt human beings, but they can leave welts on sensitive skin.

Credit: http://www.wildsingapore.com/wildfacts/cnidaria/actiniaria/gigantea.htm