Ahnfeltia plicata (Hudson) Fries

Also known as Porphyrodiscus simulans Batters, the name for the tetrasporophyte stage.
Common names: Landlady's Wig (Eng.)
Description: Gametophytes horny, cylindrical, blackish fronds, narrow (1 mm diam.), irregularly subdichotomously branched, to 120 mm high, developing from a thin crustose base of up to 200 mm diam., often buried in sand. Branches with rounded axils and blunt, often bleached tips and growing through shell fragments and sand. Tetrasporophyte (Porphyrodiscus simulans) a thin, violet crust, generally found in association with the gametophytes.
Habitat: On rock, mid-intertidal to sublittoral, especially common on sand-covered rocks, widely distributed, common.
Distribution: Widespread in the north Atlantic.
Can be confused with: Cordylecladia erecta. Much more uncommon and more regularly branched with stouter and less wiry fronds.
Usage: Used in Russia for the manufacture of Russian Agar, not utilized in Britain and Ireland.
Link: Algaebase

List of species

Photographs © M.D. Guiry