Psathyrella truncatisporoides T. Bau & J.Q. Yan, 2021

Bau, Tolgor & Yan, Jun-Qing, 2021, A new genus and four new species in the / Psathyrella s. l. clade from China, MycoKeys 80, pp. 115-131 : 115

Psathyrella truncatisporoides T. Bau & J.Q. Yan sp. nov. Figs 2i , 6

Etymology.

Referring to the truncate spore.

Type.

China. Wulingken, Baishanzhu, Qingyuan County, Lishui City, Zhejiang Province, Tolgor Bau , Jun-Qing Yan , 16 August 2015, Herbarium of Mycology , Jilin Agricultural University (HMJAU37947) .

Diagnosis.

Differs from P. rybergii by its shorter spores (6.8-7.8 μm).

Pileus 8.0-13 mm broad, spreading broadly conical to plane, hygrophanous, pale brown (7C6-7D7), white (7A1-7B1) at margin, striate up to 2/3 from margin. Veil of a thin coating of white to dirty white (7A1-7B1) fibrils, evanescent. Context thin and very fragile, same colour as pileus, approximately 1.0 mm at centre. Lamellae approximately 1.5 mm broad, pale brown (7B4-7C4), close, adnate, margin even. Stipes 10-25 mm long, approximately 1.5 mm thick, white (7A1), fragile, hollow, smooth but irregularly lumpy, with the base slightly expanding or not. Odour and taste indistinctive.

Spores (5.8)6.8-7.8(8.3) × 4.4-4.9 μm, Q=1.2-1.8, broadly ellipsoid to ellipsoid, in profile flattened on one side, inamyloid, smooth, apex obviously truncate, germ pore distinct, 1.5-2.4 μm broad. Basidia 13-17 × 6.1-7.3 μm, clavate, 4-spored. Pleurocystidia 37-49 × 12-16 μm, utriform to broadly utriform, with obtuse to broad apex, base tapering to a long or short stipe, thin-walled. Cheilocystidia 19-31 × 7.3-12 μm, abundant, similar to pleurocystidia, rarely spheropedunculate, rarely with crystals. Trama of gills irregular. Pileipellis a hymeniderm with 29-39 μm broad cells. Clamps present.

Habit and habitat.

Scattered, terrestrial, in bamboo forest.

Other specimens examined.

China. Wulingken, Baishanzhu , Qingyuan County, Lishui City , Zhejiang Province, Tolgor Bau , Jun-Qing Yan , 18 August 2015, HMJAU57045 .

Figures

Figure 2. Basidiomata a-c Heteropsathyrella macrocystidia (HMJAU 37802) d-f Psathyrella amygdalinospora (HMJAU 37952) g, h P. piluliformoides (HMJAU 37923) i P. truncatisporoides (HMJAU 37947). Scale bars: 10 mm (a-i).

Figure 6. Psathyrella truncatisporoides (HMJAU 37947) a basidiomata b basidiospores c basidia d pileipellis e pleurocystidia f cheilocystidia. Scale bars: 10 mm (a); 10 μm (b-f).