Description: Thallus monosiphonous, ecorticate and erect to 20 cms long. Much-branched pseudodichotomously, the cells becoming inflated at the ends (pyriform).

Habitat: Epiphytic or epizoic occasionally epilithic. Litteral or sublittoral to 20 m.

Distribution: Generally distributed around the British Isles including the Shetlands and the Channel Islands. Europe: Portugal, Spain, France, Baltic, Norway and the Faroes.

Similar Species: Griffithsia devoniensis has mature cells cylindrical, not pyreform.

Key Identification Features:

• Mature cells pyriform, rhizoidal filaments sparse except near the holdfast.

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

iNaturalist: Griffithsia corallinoides at iNaturalist World Species Observations database.

WoRMS: Griffithsia corallinoides at World Register of Marine Species.