How does it look like?
Actinia equina has a smooth, wart-free column with an adherent, suction cup-shaped base. It is 5-7 cm high and 6 cm in diameter. The oral disc has 6 rings of 192-200 densely arranged short, rounded-tipped tentacles that can reach 2cm in length when extended. These tentacles cannot fully retract, although they are covered when the animal contracts to protect itself or rest. The colour is variable: mostly red, brown, orange or green, usually plain all over but sometimes with blue or yellowish spots or stripes on the spine, especially with a blue line around the edge of the base.
Where does it live?
It is common on all rocky coasts and is usually found mainly at water level, although it can be submerged up to two metres deep, attached to rocks, at most 20 metres. It is also found in harbours, bridge piers and on the shells of other organisms. Very common on all coasts of Britain, all parts of western Europe, the southern Mediterranean and probably the west coast of Africa.
How does it feed?
When covered with water, it extends its tentacles, catching small fish, crustaceans and other edible particles floating in the water.
How does it reproduce?
It is a sex separated species where the female generates eggs continuously throughout the year. The eggs are fertilised inside the female, from which anemones develop and, once fully formed, young anemones are expelled outwards by means of vigorous contractions.
Is a confusion possible?
The species Actinia cari is very similar and differs mainly in its green colour and because its body wall is decorated with concentric striations. The strawberry anemone, Actinia fragacea, is also similar to Actinia equina, but is stockier and reddish to reddish-brown with greenish spots.
· It shows an aggressive behaviour towards neighbouring individuals. This aggressive behaviour is stimulated when the tentacles of adjacent anemones come into contact with each other.
· Among all European anthozoans, it is the only one capable of enduring long periods of drought at low tide. During periods of low tide it is usually contracted, forming a gelatinous ball, but when the water returns it opens up again.
· It has very stinging, blue-coloured marginal sacs, which it uses to scare off individuals of the same species if they come too close. This stinging effect is hardly noticeable to humans.
Phylum: Cnidaria, Class: Anthozoa, Order: Actinaria, Family: Actiniidae, Genus: Actinia