Radulomyces fissuratus J. H. Dong & C. L. Zhao, 2025

Dong, Junhong, Deng, Qiaohua, Chen, Minglan, Chen, Daxiang, Zhou, Chunqin & Zhao, Changlin, 2025, Molecular phylogeny and morphology reveal four new wood-inhabiting fungi of Asterostroma and Radulomyces (Basidiomycota) from Southwestern China, MycoKeys 112, pp. 35-58 : 35-58

Radulomyces fissuratus J. H. Dong & C. L. Zhao sp. nov.

Figs 5 C , 10 , 11

Holotype.

China • Yunnan Province, Dehong, Yingjiang County, Tongbiguan Provincial Nature Reserve , GPS coordinates 23°48'N, 97°38'E, altitude 1000 m asl., on the fallen branch of angiosperm, leg. C. L. Zhao, 17 July 2023, CLZhao 29670 ( SWFC).

Etymology.

fissuratus (Lat.): referring to the cracked hymenial surface of the type specimen.

Basidiomata.

Annual, resupinate, adnate, membranaceous, without odour or taste, becoming hard coriaceous upon drying, up to 30 cm long, 2 cm wide, 50–150 µm thick. Hymenial surface tuberculate, cream when fresh, turning grey to grey-buff upon drying. Sterile margin cream, thinning out, up to 1 mm wide.

Hyphal system.

Monomitic, generative hyphae with clamp connections, colorless, thin-walled, branched, interwoven, 2–3.5 µm in diameter; IKI –, CB –, tissues unchanged in KOH.

Hymenium.

Cystidia and cystidioles absent. Basidia clavate to barrelled, with 4 sterigmata and a basal clamp connection, 21.5–32.5 × 8.5–10.5 µm; basidioles dominant, similar to basidia in shape, but slightly smaller.

Basidiospores.

Globose, slightly thick-walled, smooth, colorless, CB +, (6.5 –) 7–9 (– 9.5) × (6.2 –) 6.5–8.5 (– 8.8) µm, L = 8.07 µm, W = 7.76 µm, Q = 1.01–1.06, Q m = 1.04 ± 0.03 (n = 90 / 3).

Additional specimens (paratypes) examined.

China • Yunnan Province, Dehong, Yingjiang County, Tongbiguan Provincial Nature Reserve , GPS coordinates 23°48'N, 97°38'E, altitude 1000 m asl., on the fallen branch of angiosperm, leg. C. L. Zhao, 17 July 2023, CLZhao 29695; CLZhao 29713 ( SWFC) .

Figures

Figure 5. Sections of hymenium of Asterostroma and Radulomyces A Asterostroma paramuscicola (holotype, CLZhao 8594) B Radulomyces bambusinus (holotype, CLZhao 35383) C Radulomyces fissuratus (holotype, CLZhao 26970) D Radulomyces sinensis (holotype, CLZhao 25667). 10 × 100 Oil.

Figure 10. Basidiomata of Radulomyces fissuratus in general and detailed views A, B, CLZhao 29670 (holotype) C, D CLZhao 29713 E, F CLZhao 29695.

Figure 11. Microscopic structures of Radulomyces fissuratus (holotype, CLZhao 29670) A basidiospores B basidia C basidioles D part of the vertical section of hymenium. Scale bars: 10 µm (A – D).