Description: Thallus growing as dense erect tufts to 8 cms long much branched with terete polysiphonous branches. Ecorticate with 12 - 24 pericentral cells around a large central cell.

Habitat: Very common growing on Ascophyllum nodosum rarely elsewhere.

Distribution: Widespread around the British Isles wherever A. nodosum is found. Europe: Portugal, Spain, France, Netherlands, Norway, Faroes and Iceland. Greenland. Atlantic coast of North America: Canada, Maine, New Hampshire, Massachusetts, Rhode Island, Connecticut, Long Island and New Jersey. Further afield: Baffin Bay.

Key Identification Features:

• Bushy, epiphytic on Ascophyllum nodosum.

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

iNaturalist: Polysiphonia lanosa at iNaturalist World Species Observations database.

WoRMS: Polysiphonia lanosa at World Register of Marine Species. Accepted name: Vertebrata lanosa (Linnaeus) T.A.Christensen, 1967. AphiaID: 475211.

Classification: Biota; Plantae; Biliphyta; Rhodophyta; Eurhodophytina; Florideophyceae; Rhodymeniophycidae; Ceramiales; Rhodomelaceae; Polysiphonieae; Polysiphonia