White Encrusting Zoanthid

Appearance

Zoanthids live in colony and are disk-shaped with of 0.6-1.3cm of diameter. Each polyp has a cylindrical body column with a flat oral disk at the top with two rings of short tentacles. One ring is usually held upwards while the other lies flat. Their colour ranges from white to a creamy-yellow and shades of brown. Zoanthids do not have a hard skeleton like hard corals but rather have leathery tissues which are partly composed of chitin.

Distribution

Temperate waters of the north-eastern Atlantic Ocean as well as the Caribbean Sea and western Atlantic Ocean.

Behavior

The oral cavities are usually closed when it is not feeding. It also retracts its tentacles when exposed to low tide.

Habitat

Located in places where they can grow over hard substrates like coralline algae, clam shells, hard bottoms, tide pools, reef flats and rocky shorelines.

Reproduction

Sexually by means of producing gametes, released for external fertilization as in hard corals. Asexually by budding, where polyps divide to enlarge the colony.

Defense

Zoanthids contain powerful toxins as a protection mechanism against predators.

Uses

Palytoxin is being analyzed in studies for treatment of heart disease, high blood pressure and other diseases.