Ralfsia verrucosa (Areschoug) J. Agardh
Description: Thallus a blackish-brown to burnt ochre, extensive, orbicular crust, often centrally peeling from the substrate. Thallus with a distinct margin. Thallus formed of erect filaments curving up froma prostrate system. Filaments fused, not easily separable under pressure, usually more than 10 cells long each cell with a single discoid chloroplast. Hairs present. Club-shaped multicellular (6-12 cells) paraphyses present. Unilocualr sporangia terminal in sori; plurilocular sporangia multiseriate, terminal in sori.
Habitat: upper to lower intertidal in pools on rock.