Porpomyces submucidus (Hydnodontaceae, Basidiomycota), a new species from tropical China based on morphological and molecular evidence Author Wu, Fang Author Yuan, Yuan Author Zhao, Chang-Lin text Phytotaxa 2015 2015-10-06 230 1 61 68 http://dx.doi.org/10.11646/phytotaxa.230.1.5 journal article 10.11646/phytotaxa.230.1.5 1179-3163 13632211 Porpomyces submucidus F. Wu & C.L. Zhao , sp. nov. ( Figs. 4 , 5 ) MycoBank MB 812857 Differs from Porpomyces mucidus Jülich by smaller pores (7–9 per mm) and basidiospores (2.2–2.8 × 1.2–1.8 μm). Type.— CHINA . Hainan Province , Ledong County, Jianfengling Nature Reserve, on fallen rotten angiosperm wood, 17 June 2014 , Y.C. Dai 13708 ( holotype , BJFC 017445). FIGURE 4. Porpomyces submucidu s (holotype). A basidiocarp. Etymology .— Submucidus (Lat.) referring to the resemblance with Porpomyces mucidus . Basidiome. —Annual, resupinate, up to 20 cm long, 5 cm wide, and 0.5 mm thick at the centre, soft when fresh, without odour or taste; becoming soft corky upon drying, sterile margin, cottony to rhizomorphic, thinning out, up to 2 mm . Pore surface white when fresh, becoming cream to buff when dry; pores round to angular, 7 – 9 per mm; dissepiments thin, mostly even. Subiculum white, soft corky, very thin, about 0.1 mm thick. Tubes buff, soft corky, up to 0.4 mm long. Hyphal structure. —Hyphal system monomitic; generative hyphae smooth, all septa with clamp connections, usually ampullate; hyphae unchanged in KOH. Subiculum.— Generative hyphae hyaline, thin- to slightly thick-walled, frequently branched with abundant clamp connections, loosely interwoven, IKI–, CB–, 2.5–4 μm in diam. Tubes. —Tramal hyphae hyaline, thin-walled, frequently branched with abundant clamp connections, loosely interwoven, IKI–, CB–, 2–3 μm in diam. Cystidia and cystidioles absent; basidia barrel-shaped, thin-walled with a basal clamp and four sterigmata, 6–7 × 4–5 μm; basidioles in shape similar to basidia, slightly smaller. Spores. —Basidiospores ellipsoid, hyaline, thin-walled, smooth, tapering towards the apiculus, IKI–, CB–, (2–)2.2–2.8(–3) × 1.2–1.8(–2) μm, L = 2.36 μm, W = 1.53 μm, Q = 1.54 (n=30/1). FIGURE 5. Microscopic structures of Porpomyces submucidu s (holotype). a: Basidiospores. b: Basidia and basidioles. c: Hyphae from trama. d: Hyphae from subiculum. Additional specimens examined.— Porpomyces submucidus . CHINA . Hainan Province , Ledong County, Jianfengling Nature Reserve, on fallen rotten angiosperm wood, 17 November 2007 , B.K. Cui 5183 (BJFC 003224). Porpomyces mucidus . CHINA . Shanxi Province , Jiaocheng County, Pangquangou Nature Reserve, on fallen trunk of Picea , 12 October 2004 , Yuan 860 (BJFC 000401). ITALY . Rome, Castal Fusano, on rotten wood of Pinus , 26 April 2005 , Dai 6549 (BJFC 000403). FINLAND . Etelä-Häme, Lammi Biological Station, on fallen trunk of Betula , 8 October 1992 , Dai 222 (BJFC 000402). Rigidoporus minutus . CHINA . Hainan Province , Baoting County, Diaoluoshan Nature Reserve, on rotten angiosperm, 14 June 2014 , Dai 13602A (BJFC017341), Dai 13605A (BJFC017344). Remarks. — Porpomyces submucidus is rather similar to P. mucidus , but the latter has larger pores as 4–5 per mm, fusoid cystidioles, presence of large crystals among hyphae and hymenia, and larger basidiospores measuring (2.7–) 2.8–3.9(–4.4) × (1.9–)2–2.8(–3) μm, L = 3.2 μm, W = 2.3 μm, Q = 1.3–1.4 ( Niemelä 2005 ). In addition, Porpomyces mucidus has a wide distribution in temperate areas in north hemisphere ( Gilbertson & Ryvarden 1986 , Núñez & Ryvarden 2001 , Dai 2012 , Ryvarden & Melo 2014 ), while Porpomyces submucidus is found in tropical forest in Southern China so far.