Phanerochaete citrinoalba K. Y. Luo, Yuan Yuan, Y. C. Dai & Xin Zhang 2024, sp. nov.

Phanerochaete citrinoalba K. Y. Luo, Yuan Yuan, Y. C. Dai & Xin Zhang sp. nov. Figs 4, 5 Holotype. China • Xizang Autonomous Region, Nyingchi, Sejila Mountain; on dead bamboo; 23. X. 2023; Dai 26584 (BJFC 044134). Etymology. Citrinoalba (Lat.) refers to the species having yellowish to whitish rhizomorphs. Description. Basidiomata annual, resupinate, adnate, coriaceous, without odour and taste when fresh, up to 9 cm long, 1.5 cm wide, 70–130 µm thick. Hymenial surfaces smooth, cracking, white to cream when fresh, cream to slightly buff upon drying. Becoming greyish brown in KOH. Sterile margins distinct, concolorous with hymenial surface, usually with yellowish to whitish rhizomorphas, and up to 5 mm. Hyphal system monomitic, generative hyphae mostly with simple septa, occasionally with clamp connections in subiculum, IKI –, CB –; tissue unchanged in KOH. Subicular hyphae hyaline, thin- to thick-walled, frequently simple septate, occasionally bearing clamp connections, branched at acute angles, subparallel to interwoven, 3–6 µm in diameter. Subhymenial hyphae hyaline, thin- to thick-walled, clampless, 2–3.5 µm in diameter, encrusted with crystal granules. Cystidia and cystidioles absent. Subhymenium frequently with crystal granules. Basidia clavate, with four sterigmata and a basal simple septum, 17–25 × 4–7 µm; basidioles of similar shape to basidia, but smaller. Basidiospores ellipsoid to oblong ellipsoid, hyaline, thin-walled, smooth, some with a medium guttule, IKI –, CB –, (4.7 –) 4.9–6.3 (– 6.4) × (2.2 –) 2.4–3 (– 3.1) µm, L = 5.49 μm, W = 2.66 μm, Q = 2.06 (n = 30 / 1). Type of rot. White rot.