Invertebrates
Beadlet Anemone
Actinia equina
In a rock pool on a Cornish beach, a beadlet anemone opens its short red tentacles, the ring of blue beads below them gleaming like tiny jewels.
Overview
The beadlet anemone, Actinia equina, is a Not Evaluated sea anemone of rocky shores and rock pools in the northeast Atlantic and the Mediterranean. Its red jelly-like shape, blue beads, and territorial fights make it one of the most recognisable and most studied animals of the rocky shore.
An anemone that fights for space
Patches of identical clones keep to themselves, while anemones from different clones use their blue beads to attack neighbours, leaving neat gaps between rival groups.
Status
Not Evaluated globally, though abundant on rocky shores.
Beadlet Anemone: common questions
What are the blue beads on a beadlet anemone?
They are called acrorhagi, and contain stinging cells that the anemone uses for fighting rival anemones.
Why does the beadlet anemone look like a blob at low tide?
It pulls in its tentacles at low tide, closing up into a smooth jelly-like dome to avoid drying out.
Do anemones fight?
Yes, the beadlet anemone attacks neighbouring anemones that are not clones of itself, creating clear gaps between rival groups.
Where is the beadlet anemone found?
It lives on rocky shores and in rock pools of the northeast Atlantic and the Mediterranean.