Description: Forming very small tufts to 1 mm high spreading to several cms in diameter. Erect monostromatic filaments rising from a basal network of branching filaments.

Habitat: Generally epiphytic on various algae in the low littoral and upper sublittoral.

Distribution: Widely distributed but under-recorded in the British Isles. Europe: France, Germany, Baltic Sea, Sweden, Norway, Faroes and Iceland. Greenland. Atlantic coast of North America: Canada, United States of America. Further afield: Canary Islands and the Pacific coast of South America.

Similar Species: Many other small tufted algae are similar, all require microscopic examination for identification.

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

iNaturalist: Hecatonema maculans at iNaturalist World Species Observations database.

WoRMS: Hecatonema maculans at World Register of Marine Species.