Typhrasa gossypina (Bull.) Örstadius & E. Larss., in Örstadius et al., Mycological Progress 14 (no. 25): 33 (2015)
Pileus 10–70 mm, at first conical to campanulate, then convex, finally expanded plane with umbo, when young dark brown to dark reddish brown, striate atmargin, hygrophanous, drying pale ochraceous brown, veil as fibres or flocci near the margin, appendiculate at margin. Gills broadly adnate, sometimes with tooth,mediumspaced, L=30–38, when young pale brown, becoming dark brown with white fimbriate edge. Stipe 25–100×3–10 mm, equal or thickened towards base, whitish, pulverulent at apex, with fibrils and flocci from veil remnants below, sometimes with a fugacious, hanging, striate ring. Smell none or “etwas säuerlich-kakaoartig” and taste “mild”(R. K. Schumacher pers. comm.).
Basidiospores 7–9×5–6×4.5–5.5 μm, av. 7.6–8.5×5–5.8×4.7– 5.3 μm, Qav. = 1.4–1.6 and 1.5–1.7, ovoid, subfusiform, ellipsoid, oblong, broadly ellipsoid, in profile often amygdaloid or with suprahilar depression, sometimes subphaseoliform, yellowish red (Mu. 5YR 5/8), with distinct germ pore. Basidia 4-spored, 18–30×9–11 μm. Pleurocystidia 35–80× 10–18 μm, fusiform to conical, often with a long rostrum, rarely clavate, with one, rarely two large internal oily drops, pale or rarely yellow pigmented below apex, numerous. Cheilocystidia of two types: A: similar in size, shape, and frequency to pleurocystidia, B: small, clavate, scattered to numerous; gill edge rarely faintly pigmented. Pileipellis a hymeniderm sometimes a transition to a paraderm of 15– 55 μm wide cells; pileitrama made up of pale pigmented hyphae with scattered incrustations; an intracellular pigmented layer sometimes present between pileipellis and pileitrama. Veil cells 25–120×4–10(−20) μm, cylindrical to ventricose. Clamps present.
Habitat and distribution: Solitary, gregarious or caespitose in deciduous or coniferous forests with Betula, Fagus, Quercus, Picea or Pinus, on logs, twigs, wood chips and fireplaces; rarely reported from many countries in Europe and North America.
Index Fungorum number: IF811616
Notes: Typhrasa gossypina is recognized by large rostrate cystidia with intracellular oily drop and rather wide spores. It lacks outstanding macroscopical features. The pileus is usually 10–30 mm broad but Orton (1960) measured it up to 70 mm for his Psathyrella xanthocystis. T. gossypina is separated from P. fibrillosa by the intracellular oily drop and in having pale, long rostrate cystidia. It differs from T. nanispora in having larger spores.
Figure 1. Photos of Typhrasa gossypina TL2011-389713 (C) Photo T. Laessoe.
Figure 2. Typhrasa gossypina. R.K. Schumacher 024; Pl Pleurocystidia; Ch Cheilocystidia; Basidioma ×1; Scale bars = 10 μm