Description: Hard crusts growing to 5 cms in diameter, wrinkled when dry.

Habitat: Epilithic or epiphytic on crustose corallines and Laminaria holdfasts in shallow pools of the lower littoral and in the sublittoral to 16 m.

Distribution: Generally around the British Isles. Europe: Mediterranean, Portugal, Atlantic coast of Spain and France, Baltic Sea, Norway and the Faroes. Atlantic coast of North America: Florida. Further afield: Arctic Sea including Baffin Bay, Bermuda, West Indies and Canary Islands, Cape Verde Islands, Beremuda and Jamaica.

Similar Species: Other species of Peyssonnelia.

Key Identification Features:

• Wrinkled when dry, a feature helping to distinguish from others of the genus.

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

iNaturalist: Peyssonnelia dubyi at iNaturalist World Species Observations database.

WoRMS: Peyssonnelia dubyi at World Register of Marine Species.