Description: Thallus tubular to 30 cms long and 3 cms wide, generally unbranched and somewhat flattened. Cells generally not regularly arranged except for small areas where regular arrangements may occur. Chloroplasts usually hood-shaped with one pyrenoid.

Habitat: Common. Epilithic and epiphytic in the littoral and sublittoral.

Distribution: Widespread around the British Isles. Europe: Mediterranean, Portugal, Atlantic coasts of Spain and France, Netherlands, Baltic Sea, Norway, Faroes and Iceland. West coast of Greenland. Atlantic coast of North America: Canada, Maine, New Hampshire, Massachusetts, Rhode Island, Connecticut, Long Island, New Jersey, Delaware, Maryland, Virginia, Florida. Further afield: Canary Islands, Bermuda, West Indies, Jamaica, Pacific coast of America from Alaska to California, Mexico and Chile. Generally widespread in temperate areas.

Similar Species: E. compressa is, however, branched and compressed. Microscopic examination required to confirm identification.

Key Identification Features:

• Cells not regularly arranged. Chloroplasts hood-shaped with one pyrenoid.

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

iNaturalist: Enteromorpha intestinalis at iNaturalist World Species Observations database.

WoRMS: Enteromorpha intestinalis at World Register of Marine Species. Accepted name: Ulva intestinalis Linnaeus, 1753. AphiaID: 234471.

Classification: Biota; Plantae; Viridiplantae; Chlorophyta; Chlorophytina; Ulvophyceae; Ulvales; Ulvaceae; Enteromorpha