Heteropsathyrella macrocystidia 2021

Heteropsathyrella macrocystidia T. Bau & J.Q. Yan, sp. nov.2021

MycoBank No: 838373

Holotype: China. Changbai Mountain, Antu County, Yanbian Korean Autonomous Prefecture, Jun-Qing Yan, Herbarium of Mycology, Jilin Agricultural University (HM JAU37802).

Morphological description

Sexual morph: Pileus 35–70 mm broad, obtusely conic when young, expanding to plane, with a small obtuse umbo, hygrophanous, tawny to brown, darker at center , striate up to 2/3 from margin, becoming dirty white as pileus dries. Veil scattered, small, white, fibrillose, evanescent. Context hygrophanous, thin and fragile, approximately 1.0–1.5 mm at the centre. Lamellae 3.0–6.0 mm broad, crowded, adnexed, dirty white, becoming pale brown to brown as spores mature, edge white and even. Stipe 35–100 mm long, 5.0–15 mm thick, white (7A1), cylindrical, gradually thickening towards base, fragile, hollow, but context thick, surface uneven, with small grainy bulb, covered with small, white, eva nescent fibrils. Odour and taste indistinctive. Spore print grey brown. Spores 7.8–9.2 × 4.9–5.4 μm, Q = 1.6–1.8, elongated-ellipsoid in face view, in profile flattened on one side, pale brown in water, darker brown in 5% KOH, smooth, with or without 1–2 guttules, germ pore indistinct, approximately 1.0 μm in diam. Basidia 26–34 × 7.3–9.8 μm, clavate, hyaline, 4- or 2-spored. Pseudoparaphyses abun dant and regular distribution. Pleurocystidia 59–83 × 12–20 μm, abundant, utriform with broadly obtuse apex, slightly thick-walled, glabrous or covered by irregular depos its, base tapering to a long stipe. Cheilocystidia 37–56 × 9.8–17 μm, utriform to fusoid with obtuse apex, base tapering to a short stipe. Caulocystidia 29–61 × 12–22 μm, caespitose, various, utriform, fusoid or utriform with abrupt narrow neck terminating in a capitellum, base tapering to a long or short stipe. Trama of gills irregular. Pileipel lis a 1–2-cell-deep layer of vesiculose cells, up to 61 μm long, covered by a 1-cell-deep layer of periclinal hyphae which are approximately 3.6 μm in diam and covered by scattered and irregular deposition dissolving in 5% KOH. Clamps present.

Asexual morph: Undetermined

Culture characteristics:

Habitat: Scattered on mossy rotten wood in mixed forests of larch and birch.

Distribution: China

GenBank Accession: ITS MW405102; LSU MW413359; tef-1α MW411004; β-Tub MW410997

ITS MW405101; LSU MW413358; tef-1α MW411003; β-Tub -

ITS MW405103; LSU MW413360; tef-1α MW411005; β-Tub -

Notes:

Reference: [1] Bau, T. , &  Yan, J. Q. . (2021). A new genus and four new species in the /psathyrella s.l. clade from china. MycoKeys, 80, 115-131.

Figure 2. Basidiomata a–c Heteropsathyrella macrocystidia (HMJAU37802). Scale bars: 10 mm

Figure 3. Heteropsathyrella macrocystidia (HMJAU37802) a basidiomata b basidiospores c basidia d pileipellis e pleurocystidia f cheilocystidia g caulocystidia. Scale bars: = 10 mm (a); 10 μm (b–g).