Plumose Anemone

The base of Metridium senile is considerably wider than the column and is attached to rock or another substrate. The column is long, smooth and cylindrical, of a fleshy consistency with a slimy surface lubricated with mucus. There are no warts or suckers and the column is topped by a parapet and deep groove. The oral disc is broad and deeply lobed into several curving sections that overhang the column. The slender, pointed tentacles are very numerous in larger specimens though fewer and relatively longer in smaller ones. Those near the margin are crowded and short whereas further into the disc they are longer and more dispersed. The colour range of this sea anemone is large but for any one specimen the colour is uniform throughout, except for the orange-red lip surrounding the central mouth. Colours include, white, cream, pink, orange, red, grey, brown and olive-green.

M. senile is found on the northwest coasts of Europe from the Bay of Biscay north to Norway and Iceland. It also occurs on the east and west coasts of North America and has arrived in South African waters. It is found on the lower shore and the neritic zone at depths down to about 100 m (328 ft).