Description: Thalli spherical and hollow to 20 cms across, thin and membranous not gelatinous, can be torn like paper.

Habitat: Not uncommon. Epiphytic in lower littoral rock pools and sublittoral to 3 m depth.

Distribution: Widespread on the coasts of the British Isles, but more common in the southern and western shores. Europe: Mediterranean, Portugal, Atlantic coasts of Spain and France, Belguim, Netherlands, Denmark, Baltic and Norway. Atlantic coast of North America: Canada. Further afield: Pacific coast of North America from Alaska to California, the Canary Islands, West Africa, Australia and New Zealand.

Similar Species: Leathesia difformis is also hollow, solid when young, gelatinous, never membranous and does not tear like paper. Colpomneia sinuosa is not found in the British Isles.

Key Identification Features:

• Spherical, hollow and membranous.

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

iNaturalist: Colpomenia peregrina at iNaturalist World Species Observations database.

WoRMS: Colpomenia peregrina at World Register of Marine Species. Accepted name: Colpomenia peregrina Sauvageau, 1927. AphiaID: 145856.

Classification: Biota; Chromista; Harosa; Heterokonta; Ochrophyta; Phaeophyceae; Fucophycidae; Ectocarpales; Scytosiphonaceae; Hydroclathreae; Colpomenia