Outline, phylogenetic and divergence times analyses of the genus Haploporus (Polyporales, Basidiomycota): two new species are proposed Author Zhao, Heng https://orcid.org/0000-0003-2938-5613 Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China Author Vlasak, Josef https://orcid.org/0000-0002-5363-4459 Biology Centre of the Academy of Sciences of the Czech Republic, Branisovska 31, CZ- 370 05 Ceske Budejovice, Czech Republic Author Yuan, Yuan https://orcid.org/0000-0001-6674-9848 Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China yuanyuan1018@bjfu.edu.cn text MycoKeys 2023 2023-07-24 98 233 252 http://dx.doi.org/10.3897/mycokeys.98.105684 journal article http://dx.doi.org/10.3897/mycokeys.98.105684 1314-4049-98-233 162D4756091950ECBA0EFC07B8615DEA Haploporus dextrinoideus H. Zhao, Vlasak & Yuan Yuan sp. nov. Figs 5 , 6 Etymology. dextrinoideus (Lat.): Refers to the species having dextrinoid hyphae. Type . Ecuador , Papallacta Termas , 3,300 m standing dead tree, 15 June 2021 , Josef Vlasak Jr., JV 2106/45-J ( Holotype PRM, isotypes BJFC 038566 and JV). GenBank: ITS = OQ919236 , LSU = OQ919239 . Basidiomata resupinate, annual, inseparable from the substrate, more or less corky when dry, up to 5.0 cm long, 3.0 cm wide and 0.4 mm thick at centre. Hymenophore cream bubalinus (4A2/3) to pinkish-buff (5A3) when dry, margin indistinct; pores angular to round, 1-3 per mm; dissepiments thick, entire. Subiculum slightly darker than tubes, more or less corky, up to 0.2 mm thick. Tubes pinkish-buff (5A3), hard corky. Figure 5. Basidiomata of Haploporus dextrinoideus ( Holotype , JV 2206/45-J). Scale bar: 1 cm . Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae thick-walled, branched, dextrinoid in Melzer's reagent, cyanophilous in Cotton Blue; tissues unchanged in 2% potassium hydroxide. Subicular generative hyphae hyaline, thin-walled, sometimes branched, 1.0-3.0 µm in diam.; skeletal hyphae dominant, with a wide lumen, usually branched, flexuous, interwoven, 1.5-3.0 µm in diam. Tube tramal generative hyphae hyaline, thin-walled, usually branched, 1.0-2.5 µm in diam.; skeletal hyphae dominant, with a wide lumen, usually branched, flexuous, distinctly interwoven, 1.0-3.0 µm in diam. Cystidioles fusiform with a sharp tip, thin-walled, hyaline, 19.0-35.0 x 4.5-6.5 µm . Basidia more or less capitate to pyriform, with four sterigmata and a clamp connection at base, sometimes with a few small guttules, 21.0-34.0 x 7.0-14.0 µm ; basidioles capitate to pyriform, almost the same size of basidia. Dissepimental hyphae thick-walled with one or four simple septa. Dendrohyphidia present amongst hymenium, thin-walled, hyaline. Large and irregularly-shaped crystals sometimes present amongst trama. Figure 6. Microscopic characteristics of Haploporus dextrinoideus ( Paratype , JV 2211/1-J) a basidiospores b basidia c basidioles and cystidioles d dendrohyphidia e hyphae from tube trama f hyphae from subiculum g dissepiment hyphae. Scale bars: 10 μm ( a-g ). Basidiospores oblong to ellipsoid, thick-walled, tuberculate, hyaline, some with a guttule, dextrinoid in Melzer's reagent, cyanophilous in Cotton Blue, (12.0-)13.2-19.0 x (5.0-)6.0-9.0 µm , L = 15.43 µm , W = 7.78 µm , Q = 1.98-2.16 (n = 60/2). Additional material studied. Ecuador , Papallacta Termas , 3,300 m , on unidentified angiosperm, November 2022 , Josef Vlasak Jr., JV 2211/1-J . Distribution and ecology. Haploporus dextrinoideus is known from Ecuador high mountains, 3,300 m and growing on dead unidentified angiosperm trees; causes a white rot.