Mesophyllum lichenoides (Linnaeus) Lemoine

Description: Pale to dark purple thin, brittle, leafy calcified fronds, attached at base, margins free, lobed. Fronds semicircular, concentrically banded (above). Reproduction takes place in winter and spring in small, wart-like conceptacles on the surface, persisting.
Habitat: Epiphytic on Corallina officinalis in tidal pools; S and W to Orkney Islands, occasional, locally frequent. Further south in the Atlantic, plants of this species occur on rock, but it the British Isles, the species is always epiphytic.
Key characteristics: Calcareous, thin brittle fronds with concentric markings.

Species list