Sagenidium Stirt.
Thallus felted, fluffy or rather woolly, rather loosely organised, to 10 cm diam., whitish, greyish or yellowish-white, corticolous or muscicolous. Photobiont green, Trentepohlia. Apothecia lecanorine frequent to absent, laminal, to 2 mm diam., subpedicellate, disc usually white-pruinose, margins concolorous with disc. Ascospores 8 per ascus, biseriate, colourless, fusiform, 5-7-septate.
Sagenidium is a genus of 3 species included in the family Roccellaceae. It is a Southern Hemisphere genus found in New Zealand, Tasmania and Chile. Two species are known from New Zealand [Follmann Bot. Jb. 96: 45-52 (1975)]. It is found as an epiphyte of the bark of Dacrycarpus, Dracophyllum traversii, Podocarpus and Nothofagus in shaded, humid habitats often overgrowing bryophytes. The woolly or felted texture of a greyish-white or yellowish colour is characteristic. Follmann [ Philippia 4: 34-37 (1979)] transferred taxa in Sagenidium to Byssocaulon Mont., a decision that Henssen et al. [ Lichenologist 11: 263-270 (1979)] felt to be premature. In this account such taxa are retained in Sagenidium.
