Ceriporia crassiparietata Y. C. Dai, Chao G. Wang & Yuan Yuan 2025, sp. nov.

Ceriporia crassiparietata Y. C. Dai, Chao G. Wang & Yuan Yuan, sp. nov. Figs 6, 7 Etymology. Crassiparietata (Lat.): refers to the species having a pore surface with thick dissepiments. Diagnosis. Differs from other Ceriporia species by resupinate basidiomata with white to light yellow pore surface when fresh, cream to orange-yellow when dry, angular to irregular or sinuous pores of 4–5 per mm, distinctly thick dissepiments, subicular hyphae distinctly wider than tramal hyphae, lunate to allantoid basidiospores measuring 4–4.4 × 2.1–2.3 µm. Type. CHINA • Zhejiang Province, Wuyi County, Dahongyan Forest Park, on rotten angiosperm wood, 19 June 2023, Dai 25079 (BJFC 042632, holotype). Description. Basidiomata annual, resupinate, soft, without odor or taste when fresh, consistently soft when fresh and dry, up to 3 cm long, 1 cm wide, and 0.2 mm thick at the center. Pore surface white to light yellow when fresh, becoming cream to orange-yellow upon drying; sterile margin indistinct to almost lacking; pores angular to irregular or sinuous, 4–5 per mm; dissepiments thick, entire. Subiculum very thin to almost absent. Tubes concolorous with pore surface, soft when dry, up to 0.2 mm long. Hyphal system monomitic; generative hyphae simple septate, hyaline, IKI -, CB +; tissues unchanged in KOH. Subicular hyphae thin-walled with a wide lumen, abundantly covered with large, rhombic, hyaline crystals and some oily substances, encrusted with fine crystals, frequently branched at more or less a right angle, slightly flexuous, interwoven, 5–6 µm in diam. Tramal hyphae thin-walled with a wide lumen, abundantly covered with rhombic hyaline or pale orange crystals and oily substances, encrusted with fine crystals, frequently branched, straight to slightly flexuous, subparallel along the tubes, agglutinated, 3–4.5 µm in diam. Cystidia and cystidioles absent. Basidia mostly barrel-shaped to short clavate, with four sterigmata and a simple basal septum, 9–11 × 5 µm; basidioles of similar shape to basidia, but smaller. Basidiospores lunate to allantoid, hyaline, thin-walled, smooth, IKI -, CB -, (3.8 –) 4–4.4 (– 4.6) × (2 –) 2.1–2.3 (– 2.5) µm, L = 4.08 µm, W = 2.19 µm, Q = 1.85–1.89 (n = 60 / 2). Additional specimens examined. CHINA • Liaoning Province, Fengcheng County, Tongyuanbao, on Quercus, 27 August 2006, Dai 7759 (BJFC 010215); Xizang Autonomous Region, Linzhi, Chayu County, fallen branch of Rosaceae, 27 October 2023, Dai 26986 (BJFC 044538), Dai 26988 (BJFC 044540). Notes. Ceriporia crassiparietata is closely related to the Ceriporia viridans group by sharing resupinate basidiomata with a cream, cinnamon buff, pinkish, lilac to apricot orange pore surface; subicular hyphae wider than tramal hyphae; hyphae frequently branched at a right angl; and oblong-ellipsoid, short cylindrical, lunate to allantoid basidiospores mostly wider than 1.5 µm (Wang et al. 2023). Ceriporia eucalypti Y. C. Dai & Jia J. Chen, C. gossypina Y. C. Dai, Chao G. Wang & Yuan Yuan and C. subviridans Y. C. Dai, Chao G. Wang & Yuan Yuan are similar to C. crassiparietata by having almost the same size of pores (3–5 per mm or 4–5 per mm). However, C. eucalypti has narrower basidiospores (4–4.4 × 1.1–1.4 µm vs. 4–4.4 × 2.1–2.3 µm, Chen et al. 2022); C. gossypina has a white, buff to deep olive pore surface when fresh and relatively smaller basidiospores (3.5–4 × 1.8–2 µm vs. 4–4.4 × 2.1–2.3 µm, Wang et al. 2023); and C. subviridans has a peach to apricot orange pore surface when dry, wider subicular hyphae (4.5–9 µm in diam. vs. 5–6 µm in diam., Wang et al. 2023), and relatively smaller basidiospores (3.3–3.7 × 1.8–2 µm vs. 4–4.4 × 2.1–2.3 µm, Wang et al. 2023). Ceriporia cystidiata Ryvarden & Iturr., C. microspora I. Lindblad & Ryvarden and C. otakou (G. Cunn.) P. K. Buchanan & Ryvarden share white, cream to isabelline basidiomata with C. crassiparietata. However, C. cystidiata is known from C. crassiparietata by tubular encrusted cystidia and narrower allantoid basidiospores (4–4.5 × 1 µm vs. 4–4.4 × 2.1–2.3 µm, Ryvarden and Iturriaga 2003). Ceriporia microspora is easily distinguished from C. crassiparietata by smaller ellipsoid basidiospores (3–3.5 × 1.5–2 µm vs. 4–4.4 × 2.1–2.3 µm, Lindblad and Ryvarden 1999). Ceriporia otakou differs from C. crassiparietata by larger pores (1–3 per mm vs. 4–5 per mm, Cunningham 1947) and bigger ovoid to ellipsoid basidiospores (4.5–6 × 2–2.5 µm vs. 4–4.4 × 2.1–2.3 µm, Cunningham 1947).