Hyphoderma tenuissimum C.L. Zhao & Q.X. Guan, 2021

Guan, Qian-Xin, Li, Yi-Fei & Zhao, Chang-Lin, 2021, Morphological and phylogenetic evidence for recognition of two new species of Hyphoderma (Basidiomycota) from southern China, with a key to all Chinese Hyphoderma, MycoKeys 83, pp. 145-160 : 145

Hyphoderma tenuissimum C.L. Zhao & Q.X. Guan sp. nov.

Figs 4 , 5

Holotype.

China. Yunnan Province, Chuxiong, Zixishan Forestry Park, GPS co-ordinates 25°01'26"N, 101°24'37"E, altitude 2313 m a.s.l., on fallen angiosperm branch, leg. C.L. Zhao, 1 July 2018, CLZhao 7221 (SWFC).

Etymology.

Hyphoderma tenuissimum (Lat.): referring to the thin basidiomata.

Description.

Basidioma annual, resupinate, adnate, membranaceous when fresh, hard membranaceous upon drying, up to 20 cm long, 3 cm wide, 30-100 µm thick. Hymenial surface tuberculate to minutely-grandinioid, slightly buff when fresh, buff upon drying, cracking. Margin sterile, slightly buff, 1 mm wide.

Hyphal system monomitic, generative hyphae with clamps, colourless, thick-walled, frequently branched, interwoven, 3-5 µm in diameter, IKI-, CB-; tissues unchanged in KOH.

Cystidia large, cylindrical, with 4-12 clamped septa, with abundant encrustations, 50-220 × 6.5-13 µm.

Basidia clavate to subcylindrical, constricted, somewhat sinuous, with 4 sterigmata and a basal clamp connection, 17-31 × 4.5-8 µm.

Basidiospores cylindrical, colourless, thin-walled, smooth, with oil drops inside, IKI-, CB-, 7-10.5(-11) × 3-4.5(-5) µm, L = 8.75 µm, W = 4.15 µm, Q = 2.02-2.18 (n = 120/4).

Habitat and ecology.

Climate of the sample collection site is subtropical monsoon climate area, the forest type is evergreen angiosperm forest and samples were collected on fallen angiosperm branches.

Additional specimens examined.

China. Yunnan Province, Chuxiong, Zixishan National Forestry Park, GPS co-ordinates 25°01'26"N, 101°24'37"E, altitude 2263 m a.s.l., on fallen angiosperm branch, leg. C.L. Zhao, 1 July 2018, CLZhao 6930, CLZhao 7003 (SWFC); Wenshan, Pingba Town , Wenshan National Nature Reserve , GPS co-ordinates 23°18'19"N, 104°42'47"E, altitude 1976 m a.s.l., on fallen angiosperm branch, leg. C.L. Zhao, 25 July 2019, CLZhao 16210 (SWFC) .

Figures

Figure 4. Basidiomata of Hyphoderma tenuissimum (holotype). Scale bars: 2 cm (a); 1 mm (b).

Figure 5. Microscopic structures of Hyphoderma tenuissimum (holotype) a basidiospores b basidia and basidioles c cystidia d a section of hymenium. Scale bars: 10 µm (a-d).