Melanoleuca chifengense X.D. Yu & H.B. Guo, 2021

Pei, Ying, Guo, Hong-Bo, Liu, Tie-Zhi, Qin, Wei-Qiang, Zhao, Di, Qi, Xiao-Jian & Yu, Xiao-Dan, 2021, Three new Melanoleuca species (Agaricales, Basidiomycota) from north-eastern China, supported by morphological and molecular data, MycoKeys 80, pp. 133-148 : 133

Melanoleuca chifengense X.D. Yu & H.B. Guo sp. nov. Figs 3 , 6a-c

Etymology.

The epithet refers to the species found in Chifeng City in north-eastern China.

Diagnosis.

The new species is distinguished from M. exscissa in having yellowish tinct pileus and without any type of cystidia.

Type.

China. Inner Mongolia: Chifeng City, Linxi County, Xinlin Town , Dauran Village , alt. 1200 m, 44.00°N, 118.07°E, 21 Aug 2017, H.B. Guo (SYAU-FUNGI-059) .

Description.

Pileus 30-60 mm diam., flat at first, becoming depressed at disc when mature, margin sometimes cracking, surface glabrous, grey to yellowish-grey (4B1 to 4B2), greyish-brown (4B4 to 4B6) at centre, often darker at margin. Lamellae crowded, adnate to decurrent, white to yellowish-white (4A2), 2.5-3.0 mm broad, with lamellulae, edge entire. Stipe cylindrical, 20-35 mm long × 2-5 mm diam., central, broadened at base, solid, surface grey to yellowish-grey at first (4B1 to 4B2), becoming yellowish-brown (5D8, 5E8) with age or after touching, striate, often with whitish basal tomentum. Pileus context up to 10 mm thick near stipe attachment, thin at margin, yellowish-grey (4B2), grayish brown to yellowish brown (5D3 to 5E5) in stipe cortex, up to brown (6E7) in stipe base. Odour none, taste mild. Spore print white.

Basidiospores (90/6/2) 7.0-8.5 (9.0) × 4.0-6.2(6.5) μm, av. 7.5 × 5.2 μm, Q = 1.40-1.45(1.50), ellipsoid, hyaline, amyloid, ornamentation verruculose, with irregular warts, sometimes with ridges. Basidia (20) 23-29 (30) × (7.0) 7.5-9.0 (10.0) μm, av. 26 × 8.5 μm, clavate, 4-spored, sometimes 2-spored, subhyaline. Hymenial cystidia absent, lamella edge sterile. Hymenophoral trama 42-85 μm broad, regular with thin-walled hyphae 5.5-16.5 μm diam., hyphae not pigmented. Subhymenium poorly developed. Pileipellis a cutis of numerous repent branched hyphae, 5.5-7.5 μm wide, thin-walled. Stipitipellis hyphae 3.5-8.0 μm diam., thin-walled, hyaline. Caulocystidia absent. Clamp connections absent.

Habit, ecology and distribution.

On soil or meadow outside of a forest, often on the roadside near a forest. Known from north-eastern China.

Additional specimens examined.

China. Inner Mongolia: Chifeng City, Linxi County, Xinlin Town , Dauran Village , alt. 1201 m, 44.07°N, 118.08°E, 22 Aug 2017, H.B. Guo (SYAU-FUNGI-060) .

Figures

Figure 3. Melanoleuca chifengense (holotype, SYAU-FUNGI- 059) A macroscopic habit B surface of basidiospores. Scale bars: 1 cm (A); 5 μm (B).

Figure 6. Line drawings of the three new Melanoleuca species A-C Melanoleuca chifengense (holotype, SYAU-FUNGI- 059) A basidiospores B, C basidia and basidioles D-G Melanoleuca griseoflava (holotype, SYAU-FUNGI- 062) D basidia and basidioles E caulocystidia F basidiospores G cheilocystidia H, I Melanoleuca pallidorosea (holotype, SYAU-FUNGI- 058) H basidiospores I basidia and basidioles. Scale bars: 10 μm.