Description: Thallus filamentous and very delicate, prostrate axes spread over the substrate producing erect axes up to 4 cms long. Whorl branched.

Habitat: Epiphytic, epizoic and epilithic in the intertidal to 25 m deep.

Distribution: South-west coasts of the British Isles to Argyll. Europe: Portugal to the Netherlands. Further afield: Argentina, Australia and New Zealand.

Similar Species: Other species of Antithamnionella .

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

iNaturalist: Antithamnionella ternifolia at iNaturalist World Species Observations database.

WoRMS: Antithamnionella ternifolia at World Register of Marine Species. Accepted name: Antithamnionella ternifolia (Hooker f. & Harvey) Lyle, 1922. AphiaID: 163275.

Classification: Biota; Plantae; Biliphyta; Rhodophyta; Eurhodophytina; Florideophyceae; Rhodymeniophycidae; Ceramiales; Ceramiaceae; Ceramioideae; Dohrnielleae; Antithamnionella