Morphological and phylogenetic evidence for recognition of two new species of Hyphoderma (Basidiomycota) from southern China, with a key to all Chinese Hyphoderma Author Guan, Qian-Xin Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China & College of Biodiversity Conservation, Southwest Forestry University, Kunming 650224, China Author Li, Yi-Fei College of Biodiversity Conservation, Southwest Forestry University, Kunming 650224, China Author Zhao, Chang-Lin https://orcid.org/0000-0002-8668-1075 Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China & Yunnan Academy of Biodiversity, Southwest Forestry University, Kunming 650224, China & College of Biodiversity Conservation, Southwest Forestry University, Kunming 650224, China fungichanglinz@163.com text MycoKeys 2021 2021-09-20 83 145 160 http://dx.doi.org/10.3897/mycokeys.83.69909 journal article http://dx.doi.org/10.3897/mycokeys.83.69909 1314-4049-83-145 3B4433D1A5D358C783D6E31DB8E55537 Hyphoderma puerense C.L. Zhao & Q.X. Guan sp. nov. Figs 2 , 3 Holotype. China. Yunnan Province, Puer, Jingdong County, Huilianghe Village, GPS co-ordinates 24°04'45"N , 100°56'32"E , altitude 1246 m a.s.l., on fallen angiosperm branch, leg. C.L. Zhao, 4 January 2019, CLZhao 9476 (SWFC). Etymology. Hyphoderma puerense (Lat.): referring to the locality (Puer) of the specimens. Description. Basidioma annual, resupinate, adnate, byssoid, without odour and taste when fresh, up to 15 cm long, 3 cm wide, 100-260 µm thick. Hymenial surface smooth to floccose, cream when fresh, cream to slightly buff on drying. Margin sterile, thinning out, narrow, cream. Hyphal system monomitic, generative hyphae with clamps, colourless, thick-walled, frequently branched, interwoven, 2.5-4.5 µm in diameter; IKI-, CB-; tissues unchanged in KOH; subhymenial hyphae densely covered by crystals. Figure 2. Basidiomata of Hyphoderma puerense (holotype). Scale bars: 2 cm ( a ); 1 mm ( b ). Cystidia tubular, encrusted with small crystals, 25-97 x 5.5-9.5 µm . Basidia clavate to subcylindrical, slightly constricted in the middle to somewhat sinuous, with 4 sterigmata and a basal clamp, 20-30 x 4.5-6 µm . Figure 3. Microscopic structures of Hyphoderma puerense (holotype) a basidiospores b basidia and basidioles c cystidia d a section of hymenium. Scale bars: 5 µm ( a ); 10 µm ( b-d ). Basidiospores ellipsoid, colourless, thin-walled, smooth, IKI-, CB-, (5.5-)6-7.5(-8) x 3-4.5(-5) µm , L = 6.53 µm , W = 3.71 µm , Q = 1.73-1.79 (n = 60/2). 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. 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 ). Additional specimens examined. China . Yunnan Province , Puer , Jingdong County , Huilianghe Village , GPS co-ordinates 24°04'45"N , 100°56'32"E , altitude 1246 m a.s.l. , on fallen angiosperm branch, leg. C.L. Zhao , 5 January 2019 , CLZhao 9583 (SWFC) .