Gelatinofungus brunneus Sheng H. Wu, C.C. Chen & C.L. Wei, sp. nov. Figs. 12, 13
MycoBank number: MB 840751; Index Fungorum number: IF 840751; Facesoffungi number: FoF;
Typification: TAIWAN. Nantou County, Jenai Township, Huisun Forestry Station, 24°05′40ʹ N, 121°01′17″ E, 695 m, on rotten wood, 24 Mar 2017, S.H. Wu, C.C. Chen, C.L. Wei & Y.T. Lin, GC 1703-31 (holotype TNM F31171). GenBank: ITS = LC387339; 28S = LC387344; rpb1 = LC387347; rpb2 = LC387367; tef1 = LC387385.
Etymology: brunneus (Lat.), referring to the brown hymenial surface when old and the pale brown hyphae.
Description: Basidiocarps annual, effused, adnate, ceraceous, 100–300 μm thick in section. Hymenial surface dark purplish gray with brownish tints when young, becoming cinnamon to brown when old, darkening in KOH, tuberculate, not cracked; margin paler, fairly determinate or thinning out. Hyphal system monomitic; generative hyphae nodose-septate. Subiculum fairly uniform, with compact texture; hyphae ± horizontal, pale brown, 3–5 μm diam, with 0.7–1.5 μm diam thick walls, moderately ramified, densely interwoven, agglutinated, fairly straight. Hymenial layer thickening, subhymenium clearly differentiated from subiculum, with compact texture, 80–250 μm thick;
hyphae vertical, difficult to discern, subcolorless, 2.5–4(–5) μm diam, with thin to up to 0.7 μm diam thick walls, moderately ramified, densely interwoven, agglutinated, ± flexuous, embedded in a gelatinized matrix. Brownish oily materials scattered throughout the sections. Hyphidia 10–30 × 1.5–4.5 μm, numerous, cylindrical with obtuse or acute apices, thin-walled, homogenous, often immersed. Basidia 20–38 × 5–6 μm, clavate, thin-walled, 4-sterig- mate, ± flexuous, often guttulate. Cystidia and cystidioles lacking. Basidiospores ellipsoid to broadly ellipsoid, adaxially flattened, colorless, thin-walled, smooth, often with small oily drops, inamyloid, nondextrinoid, acyanophilous, mostly 4.7–6 × 3.2–4 μm. (4.2–)4.7–6(–6.2) × (3–)3.2–4(– 4.2) μm, L = 5.2 μm, W = 3.6 μm, Q = 1.43 (n = 30) (holo- type). (4.8–)5.2–6(–6.2) × (3–)3.3–4(–4.2) μm, L = 5.5 μm, W = 3.7 μm, Q = 1.52 (n = 30) (Wu 1207-162).
Other specimens examined: TAIWAN. Taipei City, Daan District, beside National Taiwan University, on angiosperm branch, 10 Jul 2012, S.H. Wu, Wu 1207-162 (TNM F34012); ibid., Wu 1207-163 (TNM F34013).
Ecology and distribution: On angiosperm branch or rotten wood, Taiwan.
Notes: Gelatinofungus brunneus is characterized by having dark purple-gray basidiocarps with tuberculate hymenial surface, a compact subiculum with clamped, pale brown and agglutinated hyphae, absence of cystidia, presence of hyphidia, and ellipsoid to broadly ellipsoid basidiospores with small oily drops. Phlebia diaphana Parmasto ex K.H. Larss. & Hjortstam is the most similar species, but differs by having narrower subicular hyphae (1.5–2.5 μm) and presence of subulate cystidia (Hjortstam and Larsson 1986). Both Phlebia crassisubiculata Avn.P. Singh, Priyanka, Dhingra & Singla and P. dictyophoroides Sang H. Lin & Z.C. Chen also bear ceraceous basidiocarps and broadly ellipsoid basidiospores, but they are distinguished from this species by having smooth hymenophore and the presence of cystidia (Lin and Chen 1990; Singh et al. 2010).
Fig. 12 Basidiocarps of Gelatinofungus brunneus (GC 1703-31, holotype) in general and detailed views. Bars = 10 mm
Fig. 13 Micromorphological features of Gelatinofungus brunneus (drawn from GC 1703-31, holotype). a Part of vertical section from subicu- lum. b Part of vertical section from hymenial layer. c Profile of basidiocarp section. d Hyphidia. e Basidia. f Basidiospores