Description: Thallus filamentous, unbranched and attached by minute discoid holdfast. Multiseriate and terete to 20 cms long.

Habitat: On rocks and wood pilings mainly epiphytic on other algae and epizoic. From the upper littoral to 6.5 m in the sublittoral.

Distribution: Widespread in the British Isles. Europe: Mediterranean, Portugal, Spain, France, Netherlands, Baltic, Norway to Nord Kapp, Faroes and Iceland. Atlantic coast of North America: Canada, Maine, New Hampshire, Rhode Island, Connecticut and Long Island, New Jersey and Delaware. Further afield: Azores, Baffin Bay and the Canary Islands. Pacific from British Columbia to Baja California and Chile on the eastern coasts and Japan. Virtually cosmopolitan.

Similar Species: Porphyra, gametangial thallus is foliose.

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

iNaturalist: Bangia atropurpurea at iNaturalist World Species Observations database.

WoRMS: Bangia atropurpurea at World Register of Marine Species.