Psathyrella mycenoides T. Bau

Yan, Jun-Qing & Bau, Tolgor, 2018, The Northeast Chinese species of Psathyrella (Agaricales, Psathyrellaceae), MycoKeys 33, pp. 85-102 : 91

Psathyrella mycenoides T. Bau sp. nov. Figs 2f, 5

Diagnosis.

Pileus 4.0-5.0 mm, hemispherical to convex. Stipe slender. Basidiospores 8.8 –9.2(– 9.7) × 4.9-5.4 μm, germ pore distinct, but small. Pleurocystidia scattered, fusiform to lageniform with an obtuse apex. Cheilocystidia lageniform, with an obtuse apex or clavate to spheropedunculate with a long or short mucronate apex.

Holotype.

CHINA. Jilin Province, Changchun City, Jilin Agricultural University, 43°48'36"N, 125°24'25"E, 220 m alt., 10 Sep 2016, HMJAU 37888.

Etymology.

Name refers to its macroscopic characteristics similar to Mycena .

Description.

Pileus 4.0-5.0 mm, hemispherical to convex, dirty white with pinkish (7A4-7B5), hygrophanous, striate up to centre from margin. Veil not observed. Context very thin and very fragile, about 0.5 mm thick at stipe centre. Lamellae 1.5-2.0 mm broad, adnate to slightly adnexed, pale brown (7C3-7C4), edges saw-toothed under 20 × magnification. Stipe slender, 25-30 × 0.5-1.0 mm, hygrophanous, subhyaline, cylindrical, hollow, equal, fragile, evanescently pruinose at apex.

Basidiospores 8.8 –9.2(– 9.7) × 4.9-5.4 μm, Q=1.6-2.0, ellipsoid to oblong- ellipsoid, in profile flattened on one side, pale yellowish-brown in water, becoming dark grey to dark brown in 5% KOH, germ pore distinct, but small, about 0.9 μm broad. Basidia 15-17 × 8.8-10 μm, clavate, hyaline, 4- or 2-spored. Pleurocystidia 37-56 × 12-17 μm, scattered, fusiform to lageniform with an obtuse apex, thin-walled and hyaline. Cheilocystidia numerous, 29-44 × 9.8-17 μm, hyaline, lageniform with an obtuse apex or clavate to spheropedunculate, with long or short mucronate apex, rarely spheropedunculate. Trama of gills irregular, hyphae up to 10 μm broad. Pileipellis hymeniderm, cells 20-30 μm broad. Clamps present.

Habit and habitat.

Solitary to scattered on humus in mixed forests.

Other specimens examined.

CHINA. Jilin Province, Changchun City, Jilin Agricultural University, 12 Sep 2016, HMJAU 37993.