Psathyrella alpina T.Bau & J.Q.Yan, 2018

Yan, Jun-Qing & Bau, Tolgor, 2018, Psathyrella alpina sp. nov. (Psathyrellaceae, Agaricales), a new species from China, Phytotaxa 349 (1), pp. 85-91 : 86-87

Psathyrella alpina T.Bau & J.Q.Yan , sp.nov. Fig.1,2

MycoBank MB 823242

Diagnosis:—Pileus 10–30 mm, lightly brown to brown. Veil well developed in early stage. Lamellae broad with white edges. Stipe 35–40 × 4.0–5.0 mm. Spores (7.8)8.8–9.7 × 4.4–4.9 μm, ellipsoid to elongated-ellipsoid, in profile flattened on one side, germ pore distinct. Pleurocystidia 44–66 × 10–20 μm, fusiform to lageniform, with obtuse apex, rarely crystalline at apex. Cheilocystidia similar to pleurocystidia. Trama of gills parallel hyphae. Pileipellis consists of 2–3 cells deep layer of vesiculose cell, which covered a 1 cells deep layer of hyphae

Etymology:—Referring to its habit which growing in the high mountains (ALS> 1100m)

Type:— CHINA. Yunnan Province: Yuntai Mountain, Nanhua county, Yi Autonomous Prefecture of Chuxiong, N25°19′39.26″, E101°18′54.15″, ASL 2551m. Aug 11 th 2016, Tolgor Bau and Jun-Qing Yan, HMJAU37817 (Holotype!).

Description:—Pileus 10–30 mm, hemispherical, spreading convex to plane, with or without obtuse umbo, hygrophanous, striate up to 1/3 from margin, light brown to brown (7D4-7D6), becoming faint yellow brown (5C4) as pileus dries. Veil well developed in early stage, white (2A1), fibrillose, gradually disappearing in later stages. Context 1.5 mm thick towards center, gradually thinner towards margin, fragile, hygrophanous, light brown to brown (7D4- 7D6) or dirty white (2A1-2A2) while drying. Lamellae about 3.0–5.0 mm broad, moderately distant, thin, adnate, dirty white (2A1-2A2) to light brown (7C3-7C4), edges white (7A1), sawtooth under 20x magnifier. Stipe 35–40 × 4.0–5.0 mm, cylindrical, hollow, equal, fragile, surface covered with slightly white (6A1) fibrillose, evanescent. Odour and taste are indistinctive.

Spores (7.8)8.8–9.7 × 4.4–4.9 μm, Q=1.8–2.2, ellipsoid to elongated-ellipsoid, in profile flattened on one side, red brown in water, dark brown in KOH, inamyloid, smooth, 1–2 or without guttulate, germ pore distinct, 1.0–1.5 μm in diam. Basidia 20–29 × 7.3–9.8(11) μm, 4 or 2-spored (mostly 4-spored), clavate, hyaline in KOH. Pleurocystidia numerous, 44–66 × 10–20 μm, fusiform to lageniform with an obtuse apex, rarely adhering subhyaline deposits at apex, hyaline, thin-walled. Cheilocystidia scattered, similar to pleurocystidia, 27–42 × 7.3–12 μm. Lamellae trama hyphae parallel, 7.0-12 μm broad, cylindrical, hyaline, thin-walled. Pileipellis consists of vesiculose cell, 25–37 μm diam, covered by a one cell deep layer of hyphae, 4.0–5.0 μm width.

Habit and habitat:—Solitary to caespitose on soil in broad-leaved forest.

Additional Material examined: CHINA. Yunnan Province: Yuntai Mt., Nanhua county, Yi Autonomous Prefecture of Chuxiong , N25°19′39.26″, E101°18′54.15″, ASL 2551m. Aug 11 th 2016, Tolgor Bau and Jun-Qing Yan, HMJAU37818 ; Jiangxi Province: Matou Mt., Zixi Town, Fuzhou City , N27°47′24.45″, E117°12′57.12″, ASL 1100m. Aug 11 th 2015, Tolgor Bau and Jun-Qing Yan, HMJAU37819 .