Inonotus subglobisporum J. L. Zhang, H. M. Zhou & C. L. Zhao, 2025

Zhang, Jianling, Gu, Zirui, Zhou, Chunqin & Zhou, Hongmin, 2025, Molecular phylogeny and morphology reveal four new species in Hymenochaetales and one new species in Cantharellales from Southwestern China, MycoKeys 115, pp. 87-135 : 87-135

Inonotus subglobisporum J. L. Zhang, H. M. Zhou & C. L. Zhao sp. nov.

Figs 9 , 10

Diagnosis.

Inonotus subglobisporum differs from I. radiata by its perennial basidiomata, laterally stipitate, polygon pores, tapered, dark brown, thick-walled setae, and subglobose, thick-walled, hyaline basidiospores.

Holotype.

China • Yunnan Province, Puer, Jingdong County, Ailaoshan National Nature Reserve , 23°42'N, 101°52'E, evel. 2450 m asl., on fallen angiosperm trunk, 25 August 2018, CLZhao 8765 ( SWFC).

Etymology.

Subglobisporum (Lat.) refers to the subglobose basidiospores.

Description.

Basidiomata. Perennial, laterally stipitate, solitary, without odor or taste when fresh. Pilei fan-shaped, cortical to cork, extend up to 1.3 cm long, 2.2 cm wide, and 6 mm thick in diam at the base. Pileal surface honey-yellow to fuscous when fresh, vinaceous brown to fuscous when dry. Pore surface cream, when fresh, becomes cream to fawn when dry; pores polygonal, 4–6 per mm. Context cinnamon-buff when dry, cork, up to 5 mm thick. Tubes cream to fawn when dry, cork, up to 1 mm long. Stipe with the same color as pores, up to 23 mm long and 15 mm in diameter when dry.

Hyphal structure. Monomitic; generative hyphae, simple-septate, slightly thick-walled, frequently branched, interwoven. Generative hyphae in the tube frequent, brownish, slightly thick-walled, easily collapsing, 2.5–5.0 µm in diam. Generative hyphae in the context frequent, brown, slightly thick-walled, 3.0–7.0 µm in diam, IKI –, CB –; tissues brownish in KOH. Context. Setae numerous, tapered, dark brown, thick-walled, strongly encrusted in the surface, and almost entirely buried, 12.0–69.5 × 4.0–11.0 μm, cystidoles absent. Basidia clavate, with four short sterigmata and a basal simple-septate, 5.5–13.0 × 2.5–6.5 μm; basidioles in shape similar to basidia, but slightly smaller. Basidiospores. Subglobose, hyaline, thick-walled, smooth, IKI –, CB +, (3.5 –) 3.6–4.3 (– 4.4) × (2.6 –) 2.8–3.5 (– 3.6) μm, L = 3.99 μm, W = 3.20 μm, Q = 1.22–1.27 (n = 120 / 4).

Other specimens examined.

China • Yunnan Province, Puer, Jingdong County, Ailaoshan National Nature Reserve , 23°42'N, 101°52'E, evel. 2450 m asl., on fallen angiosperm trunk, 23 August 2018, CLZhao 8331; CLZhao 8387; CLZhao 8433; CLZhao 8543; 24 August 2018, CLZhao 8500; 25 August 2018, CLZhao 8678; CLZhao 8737; CLZhao 8789 ( SWFC) .

Figures

Figure 9. Basidiomata of Inonotus subglobisporum (holotype, CLZhao 8765) A, B the front of the basidiomata C, D characteristic hymenophore. Scale bars: 1 cm (A, C); 1 mm (B, D).

Figure 10. Microscopic structures of Inonotus subglobisporum (holotype, CLZhao 8765) A basidiospores B basidia and basidioles C setae D hymenium and hyphae from trama E hyphae from context. Scale bars: 5 μm (A); 10 μm (B – E); 10 × 100 oil.