Description: Thallus tough and leathery to about 40 cms long with branches 1 cm wide and a clear midrib. The frond margins are entire with rounded tips. There are no air vesicles in the frond, the receptacles are terminal with a narrow rim or margin. When held up the frond can usually be seen to have a spiral twist.

Habitat: Epilithic. Common on most rocky shores below the Pelvetia and the Ascophyllum and Fucus vesiculosus zones.

Distribution: Common on almost shores of the British Isles. Europe: Azores, Poprtugal, Spain, France, Netherlands, Baltic, Norway, Faroes, Jan Mayen and Bjornoya and Iceland. Atlantic coast of North America: Canada, Maine, New Hampshire, Massachusetts, Rhode Island, Connecticut and Long Island and Delaware. Further afield: the Canary Islands, Rio-de-Oro, Spanish West Africa, Spanish Sahara and Western Sahara.

Similar Species: Similar to young Fucus vesiculosus when sterile.

Key Identification Features:

• Without air vesicles, smooth edge to the frond often with a spiral twist.

Distribution Map from NBN: Fucus spiralis at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Fucus spiralis at iNaturalist World Species Observations database.

WoRMS: Fucus spiralis at World Register of Marine Species.