Cerioporus yunnanensis

Cerioporus yunnanensis Y. Yang and C.L. Zhao

MycoBank number: 851226

Basidiomata Annual, pileate, odorless when fresh, hard corky when dry. Pileus applanate to triquetrous, up to 2 cm long, 1 cm wide, and 5 mm thick at base. Pileal surface fawn brown to black, distinctly sulcate, and margin obtuse. Pore surface white when fresh, becoming white to cream when dry, sterile margin distinct, up to 1 mm wide, pores round, 2–3 per mm. Context cinnamon brown to fawn brown, corky, up to 2 mm thick. Tubes cream to brown, hard corky, distinctly stratified, up to 3 mm long. Hyphal system Dimitic; generative hyphae with clamp connections, thin-walled, colorless, 2–3 μm in diameter; skeletal hyphae dominant in context, thick-walled with a narrow lumen to subsolid, colorless, 2.5–4 μm in diameter; all hyphae occasionally branched, flexuous, interwoven, IKI–, CB–, tissues unchanged in KOH. Hymenium Cystidia absent, but fusoid cystidioles present, colorless, thin-walled, 17–30 × 5–8 μm; basidia clavate, with four sterigmata and a basal clamp connection, 21–35 × 6–10 μm; basidioles in shape similar to basidia, but slightly smaller. Spores Basidiospores cylindrical, colorless, thin-walled, smooth, with oil droplets inside, IKI–, CB–, (8–)9–12.5 × 3.5–5(–6) μm, L = 10.62 μm, W = 4.30 μm, Q = 2.47–2.61 (n = 60/2).

Additional specimen examined (paratype): China, Yunnan Province, Qujing, Zhanyi District, Xiajia Village. GPS coordinates: 25◦44′ N, 103◦36′ E; altitude: 1950 m asl., on fallen angiosperm branches, leg. C.L. Zhao, 6 March 2023, CLZhao 27228 (SWFC).

Fig. 1 Maximum parsimony strict consensus tree illustrating the phylogeny of three new species and related species in Polyporales based on ITS + nLSU + mt-SSU + TEF1 + RPB1 + RPB2 sequences. Branches are labeled with maximum likelihood bootstrap values ≥ 70%, parsimony bootstrap values ≥ 50%, and Bayesian posterior probabilities ≥ 0.95. The new species are in bold.