Hyphoderma fulgens W. Li and C. L. Zhao sp. nov.

Figs 12, 13

Typification.

China • Yunnan Province: Dehong, Yingjiang County, Tongbiguan Provincial Nature Reserve, GPS coordinates 24°30'N, 97°30'E, altitude 1006 m asl., on fallen angiosperm branch, leg. C. L. Zhao, 3 July 2024, CLZhao 37429 (SWFC 00037429), GenBank: ITS = PV 829544; nLSU = PV 810095.

Etymology.

fulgens (Lat.): refers to the shiny color of the hymenial surface of the specimens.

Description.

Basidiomata. Annual, resupinate, adnate, membranaceous, without odor or taste when fresh, up to 9 cm long, 1.8 cm wide, and 100 μm thick. Hymenial surface smooth, white to cream when fresh, white when dry. Sterile margin narrow, white, up to 1 mm.

Hyphal system. Monomitic; generative hyphae with clamp connections, colorless, thin-walled, branched, interwoven, 2.5–3.2 µm in diameter, IKI –, CB –, tissues unchanged in KOH.

Hymenium. Cystidia clavate, colorless, thin-walled, smooth, encrusted, 30.4–37.1 × 5.5–7.5 µm. Basidia barreled, thin-walled, smooth, slightly flexuous, with four sterigmata and a simple septum at the base, 21.5–26 × 5.5–8 µm; basidioles similar to basidia in shape but slightly smaller.

Spores. Basidiospores subcylindrical, colorless, thin-walled, smooth, with oil droplets inside, IKI –, CB –, (7 –) 7.5–11.5 × (2 –) 2.5–4 µm, L = 9.55 µm, W = 3.39 µm, Q = 2.74–2.89 (n = 120 / 4).

Additional specimens examined (paratypes).

China • Yunnan Province: Dehong, Yingjiang County, Tongbiguan Provincial Nature Reserve, GPS coordinates 24°30'N, 97°30'E, altitude 1006 m asl., on fallen angiosperm branch, leg. C. L. Zhao, 19 July 2023, CLZhao 30254 (SWFC 00030254); 2 July 2024, CLZhao 37266 (SWFC 00037266); • Mang City, Tongbiguan Provincial Nature Reserve, GPS coordinates 24°42'N, 97°54'E, altitude 1006 m asl., on fallen angiosperm branch, leg. C. L. Zhao, 29 June 2024, CLZhao 36600 (SWFC 00036600); 8 July 2024, CLZhao 39677 (SWFC 00039677); CLZhao 39618 (SWFC 00039618); CLZhao 39474 (SWFC 00039474).

Notes.

In the phylogenetic analysis, the specimens of Hyphoderma fulgens (CLZhao 37429, CLZhao 30254, CLZhao 36600, CLZhao 39474) formed a closely related sister relationship to H. amoenum (Burt) Donk (USO 286622), with 99 % ML, 89 MP bootstrap support, and a 0.99 BYPP value. However, morphologically, H. amoenum differs from H. fulgens by having wider basidiospores (9–13 × 5–6 µm vs. 7.5–11.5 × 2.5–4 µm; Tellería et al. 2012). Morphologically, H. fulgens is similar to H. guangdongense and H. tenuissimum by having subcylindrical basidiospores (Guan and Zhao 2021 a; Su et al. 2024). However, H. guangdongense is distinguished from H. fulgens by its farinaceous hymenial surface and septate cystidia (Su et al. 2024). In addition, H. tenuissimum differs from H. fulgens by its tuberculate to minutely grandinioid hymenial surface and larger cystidia (50–220 × 6.5–13 µm vs. 30.4–37.1 × 5.5–7.5 µm; Guan and Zhao 2021 a). These morphological and phylogenetic data indicate that our collections represent a new species, Hyphoderma fulgens.