The Anthozoa contain about 7500 species and are therefore the largest class of Cnidaria. Anthozoa are found exclusively in the sea and live there in depths down to 6000m.
They provide a big part of the colour splendour when diving around the canary islands.
Most of the Anthozoa are tightly bound to their location. In order to hold to the ground, they have a suction pad or are otherwise anchored in the ground. However, there are also moving species such as the Berried Anemone.
Anthozoa have a cylindrical body with a mouth being surrounded by tentacles. The tentacles are filled with nettle cells to paralyse their prey. Sense organs are not present. However, they have sense cells, which occur mainly on the oral cavity and tentacles.
By the way, some of them are poisonous. The poison of some Zoantharia can be deadly, for example.
Distribution and Habitat
They are found all over the world in all seas. Depending on the species, they live from the tidal zone to a depth of 6000m. While some species prefer dark, hidden places, other species are found in open places with lots of current.
The subclass of Hexacorallia is divided into six orders and contains about 4000 species. Hexacorallia, because they have either six tentacles or a multiple of six. Although some of them live solitary, a large part of them are found in colonies. These are sometimes connected to each other by tubes or the soft part of their body.
The Sea Anemones are an order of the Anthozoa and are also often referred to as water lilies or actinias. There are about 1200 known species, which occur exclusively in the sea and are spread to the deep sea as well.
Antipatharia – Black Corals
The Black Corals are an order of Anthozoa with about 230 known species. They live mostly in tropical seas, at depths over 100m. There is only one species known to me in the Canary Islands.
The Corallimorpharia are an order of the Anthozoa with about 40 known species. The taxonomy of Corallimorpharia is still very uncertain and inadequately studied. The species live all over the world in all seas and are predominantly characterized by a large oral disc.
The Zoantharia are an order of the Anthozoa with about 300 known species. Zoantharia mostly form colonies, but there are also solitary species. They occur mainly in tropical and subtropical seas. The individual polyps are rarely larger than 2cm. However, colonies can populate several m².
The Octocorallia are a subclass of the Anthozoa, which covers about 3200 species. Octocorallia, because the polyps always have eight feathered tentacles and eight septa.
Their food consists almost entirely of phytoplankton. Often they stand transversely to the main current. This allows them to absorb as much food as possible. Because they are firmly attached to their location, they can only defend themselves badly. For this reason, many eight-ray paints produce poisonous or disgusting substances.