Cap up to 20 mm across, conical to convex, flattening with age, mostly with a prominent umbo, translucent-striate, sulcate, hygrophanous, fairly dark grey with a darker, greyish brown to almost black centre, the margin paler to whitish. Taste not recorded. Gills 26-30 reaching the stem, ascending, adnexed, with or without a short decurrent tooth, somewhat intervenose with age, grey to dark grey, the edge convex, paler. Stem up to 50 x 3 mm, cylindrical, glabrous (at least in older specimens), pale grey at the apex, darker greyish downwards, paler than the cap, the base densely covered with long, coarse, flexuous, whitish fibrils. Odour nitrous. Basidia 29-35 x 8-9 µm, clavate, 4-spored, with sterigmata 9-12 µm long. Spores 9.3-11(-12.5) x 5-6.5 µm, Qav ˜ 1.8, pip-shaped, smooth, amyloid. Cheilocystidia 50-103 x 13-24 x 3.5-6.5 µm, occuring mixed with basidia, fusiform, smooth. Pleurocystidia numerous, similar. Lamellar trama dextrinoid. Hyphae of the pileipellis 2.7-6.3 µm wide, covered with simple to very much branched excrescences 2.5-22.5 x 2 µm which tend to become covered with gelatinous matter; terminal cells 45-70 x 12.5-24 µm, variously shaped, subcylindrical, fusiform, clavate, frequently covered with coarse excrescences 4.5-11 x 2.5 µm. Hyphae of the cortical layer of the stem 1.8-2.5 µm wide, smooth to sparsely covered with simple, cylindrical excrescences 1.8-4.5 x 1.8-2.5 µm; terminal cells (caulocystidia) 2.5-10 µm wide, with few to fairly numerous, coarse excrescences. Clamps absent.
Ecology and distribution
Terrestrial among grass and fallen leaves under Salix. One record outside the type locality in South Norway. Autumn.