Green Sea Mat

(Zoanthus sp.)




Facts about this animal

Sea mats are colonial anemones, which use rocks as substrate, which they will encrust as they propagate.

Some sea mats are brightly coloured with green seemsing to be the most common colour. They have oral disks that are less than 2 centimeters in diameter. This flat disk is surrounded by two rows of short tentacles. The polyps are distinguished from other Zoanthids by their divided sphincter muscles. The polyps grow out of a thick mat made of gelatinous material.

Sea mats live in symbiosis with microscopic, single-celled marine algae or dinoflagellates called zooxanthellae, and derive much of their energy from the products these zooxanthellae generate by photosynthesis. Sea mats are not known to actively "feed" on anything, but rather passively absorb dissolved organics from the water column directly through their "skin."

Sea mats contain a potent neurotoxin called Palytoxin.

Did you know?
that Zoanthids mainly reproduce asexually, although there is a limited amount of sexual reproduction? Asexual reproduction is by budding, which is the creation of a new polyp from an old polyp, and fission, where the stolons disintegrate and a new fragment is formed. A colony is generally genetically the same, as there is little fusion of colonies or recruitment to a old colony. Even when a colony is sexually reproductive, a large proportion of polyps remain infertile, which demonstrates the greater importance of asexual reproduction and growth.


Name (Scientific) Zoanthus sp.
Name (English) Green Sea Mat
Name (French) Anémone encroutante
Name (German) Krustenanemone
Name (Spanish) Zoanthus
CITES Status Not listed
CMS Status Not listed



Photo Copyright by
Vishal Bhave



Range Zoanthus alderi Zoanthus kealakekuaensis: Central Pacific Zoanthus pacificus: Central Indo-Pacific Zoanthus pulchellus: Indo-Pacific Zoanthus sociatus: Caribbean
Habitat Tropical and subtropical seas, on rocks, coral reefs.
Wild population No data
Zoo population 27 zoos or aquariums reported Zoanthus, including unspecified, pulchellus and sociatus to ISIS (2008)

In the Zoo

Green Sea Mat


How this animal should be transported

For air transport Container Note 56 of the IATA Live Animals Regulations should be followed. There is no Container Requirement for pupae.


Find this animal on ZooLex


Photo Copyright by
Vishal Bhave

Why do zoos keep this animal

Zoos and aquariums keep the flower-like sea mats for educational reasons as part of their efforts to familiarise visitors with invertebrate biodiversity.