Sea Mat Zoanthid

Appearance

This zoanthid is in the form of an encrusting cushion, with a rubbery texture, the surface of which is thick and marked by the opening of polyps slightly raised from the surface, with a maximum diameter of 2 cm. The color is caramel brown. The polyps when opened, have tentacles on the outer border and a large oral disc. When closed, they fit into the common base, leaving a surface of small rounded lobes with a small pleated hole at the top. It can form large colonies of 1 m². Size 10 cm -1 m².

Distribution

Indo-West Pacific Ocean: Red Sea, Madagascar, Japan, and Australia.

Behavior

It lives in symbiosis with microscopic algae, the zooxanthellae. It is aggressive with other corals.

Habitat

It is found on shallow coral reefs. Depth 1-15 m. It is often found in areas where waves crash onto the rocks in shallow waters. When the animals find a happy spot, the colony can cover a large area.

Reproduction

The "Brachycnemina" colonies are generally hermaphroditic. The fertilized eggs are released through the mouth of the polyp, in tightly packed clusters, which give rise to planktonic larvae which will colonize the substrate.

Food

It feeds on zooxanthellae which provide, by photosynthesis, food in exchange for shelter. It supplements its food intake by capturing zooplankton with the help of its tentacles.

Defense

Their mucus coating contains a toxin, palytoxin, which is fatal to fish and dangerous to humans. It is believed that the toxins are not produced by the animal but by bacteria that live in symbiosis with the polyps. It is used to protect itself from predators and also clear the path of other corals so as to make space for expanding its colony. This toxic mucus enters your eye, mouth, or an open wound, it can cause various disorders including numbness, hallucinations, or even death.