Description: The typical frond is readily identified by the air vesicles which occur in pairs one on either side of the midrib. However the species is very variable. Typical plants may be grow to over 1 m long and 2.5 cms wide with a clear midrib. Spherical air vesicles, 5 to 10 mm in diameter, occur in pairs one on either side of the midrib. Receptacles are terminal.

Habitat: Common. Epilithic between, but overlapping with, Ascophyllun nodosum and Fucus serratus. Recorded in the low salinity of the Baltic.

Distribution: Common on all but the most exposed shores of the British Isles. Europe: Portugal, Spain, France, Netherlands, Baltic, Sweden, Norway, Finland, Faroes, Spitzbergen and Iceland. Greenland. Atlantic coast of North America: Canada, Maine, New Hampshire, Massachusetts, Rhode Island, Connecticut and Long Island, New Jersey, Delaware, Maryland and Virginia. Further afield: Canary Islands.

Similar Species: The air bladders make the typical specimen readily identified. Ascophyllum nodosum also has airbladders, however these do not occur in pairs and Ascophyllum has no midrib. Specimens from exposed shores may not have air bladders and may be not be so easily determined.

Key Identification Features:

• Typical specimens show air vesicules in pairs on the frond one on either side of the midrib.

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

iNaturalist: Fucus vesiculosus at iNaturalist World Species Observations database.

WoRMS: Fucus vesiculosus at World Register of Marine Species. Accepted name: Fucus vesiculosus Linnaeus, 1753. AphiaID: 145548.

Classification: Biota; Chromista; Harosa; Heterokonta; Ochrophyta; Phaeophyceae; Fucophycidae; Fucales; Fucaceae; Fucus