This common European species is not a true anemone. Instead of attaching itself to a rock it lives in a soft tube protruding above sand or mud.
The animal's tentacles are usually all that are visible. The inner set circle the mouth and are short and stiff. The long, flexible, attractive outer ones, over 100 of them, sweep prey inwards. When disturbed the whole anemone shoots back into its tube, like a tubeworm. The tentacle crown measures up to 10 cm across.
The burrowing anemone lives from the shallows down to 100 m. The tentacles may be white, brown, green or banded.
You find this tube anemone from Norway down to the Bay of Biscay.
Photo credit: Tim Nicholson