Description: Thallus foliose growing from minute holdfast. Blade monostromatic to 18 cms long and 4 to 6 cms broad.

Habitat: Common. Epilithic on rock, concrete or wood etc, from the upper littoral to above high water.

Distribution: Widespread around the British Isles. Europe: Portugal, Spain, France, Netherlands, Baltic, Norway the Faroes and Iceland. Atlantic coast of North America: Canada, Maine and New Hampshire. Further afield: Azores.

Similar Species: Other species of Porphyra.

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

iNaturalist: Porphyra linearis at iNaturalist World Species Observations database.

WoRMS: Porphyra linearis at World Register of Marine Species. Accepted name: Porphyra linearis Greville, 1830. AphiaID: 144431.

Classification: Biota; Plantae; Biliphyta; Rhodophyta; Eurhodophytina; Bangiophyceae; Bangiophycidae; Bangiales; Bangiaceae; Porphyra