FAGACEAE. Nothofagus fusca: Nelson, Staircase Creek, Reefton, 700 m.

Hymenophore annual, sometimes reviving a second season, loosely attached, effused forming linear areas to 10 x 2 cm; hymenial surface ferruginous, becoming umber, sepia, or olivaceous, velutinate, even, not creviced; margin thinning out, adherent, strongly fibrillose, pallid tan. Context to 500 µm thick, ferruginous, of intertwined hyphae not differentiated into intermediate and basal layers; generative hyphae 4-6 µm diameter, walls 0.5 µm thick, chestnut, branched, inflated to 12 µm inoccasional cells, coated with sparse gelatinous warts. Cordons numerous, scattered in the base, formed from 7-28 partly cemented hyphae. Septocystidia arising in the base of the hymenial layer and projecting to 10 µm, also scattered in the context, cylindrical, septate, 80-180 x 10-16 µm, walls chestnut, 1-3 µm thick, coated with granules of mucilage arranged in irregular warts. Hymenial layer to 120 µm deep, a dense palisade of basidia, paraphyses, septocystidia, and paraphysate hyphae. Basidia subclavate, 30-45 x 6-8 µm, bearing 2-4 spores; sterigmata arcuate, to 6 µm long. Paraphyses subclavate, 18-30 x 5-6 µm. Paraphysate hyphae 4-6 µm diameter, hyaline, slender, septate, projecting to 40 µm. Spores obovate, elliptical, pip-shaped, or naviculate, often flattened on one side, apices rounded or slightly acuminate, bases apiculate, 10-13 x 5-7 µm, walls smooth, ferruginous or chestnut, 0.5 µm thick.

DISTRIBUTION: Europe, Great Britain, North America, South Africa, New Zealand.

HABITAT: Bark of decayed branches and trunks.

Readily recognised by the large septocystidia which may project for as much as 110 µm and give to the hymenial surface its velutinate appearance. Hyphae of the context are brown, frequently inflated between septa, and near the base often compacted into cordons. Spores vary appreciably in shape and size. Although Bourdot & Galzin (1928, p. 362) recorded the presence of rare clamp connections, they were not seen in specimens examined in Kew herbarium, nor in collections from this region. As the synonymy shows, based for the most part on the list given by Rogers & Jackson (1943, p. 273), the species bears many names, erected mainly on slight differences in shape and size of septocystidia, or colour variants of the hymenial surface.

TYPE LOCALITY: Europe.