Nigroporus yunnanensis Y. C. Dai, X. L. Li & Yuan Yuan, 2025

Nigroporus yunnanensis Y. C. Dai, X. L. Li & Yuan Yuan sp. nov.

Figs 9 View Figure 9 , 10 View Figure 10

Holotype.

China • Yunnan Province: Baoshan County, Baihualing Forest Park , on fallen angiosperm trunk, 21 September 2018, Dai 19116 ( BJFC 027585 About BJFC ).

Etymology.

Yunnanensis (Lat.): refers to the species being found in Yunnan Province, southwest China.

Description.

Basidiomata. Annual, effused-reflexed to pileate, leathery and without odor or taste when fresh, becoming woody hard upon drying, up to 8.5 cm long, 4 cm wide when resupinate; pilei semicircular, projecting up to 1 cm, 1.5 cm wide and 2.5 mm thick at base. Pileal surface brown when fresh, becoming liver brown to dark brown upon drying, concentrically zonate, glabrous, margin thin. Pore surface vinaceous to brownish vinaceous when fresh, become purplish date when bruised, russet when dry; sterile margin distinct, white when fresh, and cream when dry, up to 0.5 mm wide; pores round to angular, 7–10 per mm; dissepiments thin, lacerate. Context liver brown, hard corky when dry, up to 1.5 mm thick. Tubes concolorous with pore surface, corky when dry, up to 1 mm long.

Hyphal structure. Hyphal system dimitic; generative hyphae bearing clamp connections; skeletal hyphae IKI –, CB –; tissues darkening in KOH.

Context. Generative hyphae hyaline, thin-walled, occasionally branched, 1.5–4 µm in diam.; skeletal hyphae dominant, yellowish brown, slightly thick-walled with a wide lumen, unbranched, slightly flexuous, interwoven, 3–4.5 µm in diam.

Tubes. Generative hyphae hyaline, thin- to slightly thick-walled, occasionally branched, 2.5–4.5 µm in diam.; skeletal hyphae dominant, yellowish brown, thick-walled with a wide to narrow lumen, unbranched, slightly flexuous, interwoven, 4–5 µm in diam. Cystidia absent; cystidioles present, fusoid, hyaline, thin-walled, smooth, 7.5–11 × 2.5–4 µm. Basidia barrel-shaped, with four sterigmata and a basal clamp connection, 5–7.5 × 3–4.5 µm; basidioles of similar shape to basidia, but smaller.

Spores. Basidiospores allantoid, hyaline, thin-walled, smooth, occasionally with one or two guttules. IKI –, CB –, (3.8 –) 4–4.5 (– 5) × (1.8 –) 1.9–2.2 (– 2.5) µm, L = 4.19 µm, W = 2.03 µm, Q = 2.06–2.09 (n = 90 / 3).

Additional specimens examined

(paratypes). China • Yunnan Province, Pingbian County, Daweishan National Forest Park , on fallen angiosperm branch, 27 June 2019, Dai 19870 ( BJFC 031544 About BJFC ) . • Tengchong County, Gaoligongshan, Dahaoping , on dead angiosperm tree, 10 November 2019, Cui 18205 ( BJFC 035064 About BJFC ) .