Invertebrates
Common Starfish
Asterias rubens · also called common sea star
On a mussel bed at low tide, a common starfish hunches over its prey, its orange arms wrapped around the shell as its tube feet haul the two halves apart.
Overview
The common starfish, Asterias rubens, is a Not Evaluated starfish of rocky shores, rock pools, mussel beds, and seabeds in the northeast Atlantic. Its tube feet, its stomach-outside way of eating, and its ability to regrow arms make it one of the best-known animals of the European seashore.
A hunter with its stomach outside
Instead of swallowing a mussel whole, the starfish pushes its stomach into a tiny gap in the shell and digests the animal in place, a technique that lets it eat prey larger than its mouth.
Status
Not Evaluated globally, though widespread and abundant.
Common Starfish: common questions
How does a starfish eat a mussel?
It pulls the shell open slightly with its tube feet, then pushes its stomach into the gap to digest the animal inside.
Can a starfish regrow its arms?
Yes, it can regrow a lost arm, which it may shed to escape a predator.
How does it move?
It moves and grips with hundreds of tiny tube feet along the underside of each arm, which work by water pressure.
Where is the common starfish found?
It lives on rocky shores, in rock pools, on mussel beds, and on seabeds in the northeast Atlantic, from the White Sea and Norway to West Africa.