Description: A small filamentous erect alga, growing in tufts to 4 cms long. Main axis with transverse and longitudinal divisions ending with a large apical cell.

Habitat: Not uncommon, epilithic and epiphytic in the littoral.

Distribution: Widely distributed around the British Isles. Europe: Portugal, Spain and France. Atlantic coast of North America: Canada, Maine, New Hampshire, Massachusetts and Virginia. Further afield: Canary Islands and Liberia.

Similar Species: Most species of Sphacelaria, and other small branched brown algae, are very alike and require microscopic examination for identification.

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

iNaturalist: Sphacelaria fusca at iNaturalist World Species Observations database.

WoRMS: Sphacelaria fusca at World Register of Marine Species. Accepted name: Sphacelaria fusca (Hudson) S.F.Gray, 1821. AphiaID: 145893.

Classification: Biota; Chromista; Harosa; Heterokonta; Ochrophyta; Phaeophyceae; Dictyotophycidae; Sphacelariales; Sphacelariaceae; Sphacelaria