Tomentella fuscopelliculosa H.S. Yuan, X. Lu & Y.C. Dai, sp. nov.
Index Fungorum number: IF555743; MycoBank number: MB 555743; Facesoffungi number: FoF 05623; Figs. 1, 2, 3
Etymology – Refers to the brown and pelliculose basidiocarps.
Holotype – IFP 019285.
Basidiocarps annual, resupinate, adherent to the substrate, pelliculose, without odour or taste when fresh, 0.8–1.5 mm thick, continuous. Hymenophoral surface smooth, brown to dark brown (6E5–6F5) and lighter than subiculum when dry. Sterile margin often indeterminate, farinaceous, concolorous with hymenophore. Rhizomorphs absent. Subicular hyphae monomitic; generative hyphae clamped and rarely simple septate, thick-walled, occasionally branched, 3.5–5 μm diam, without encrustation, pale brown in KOH and in distilled water, cyanophilous, inamyloid. Subhymenial hyphae clamped and rarely simple septate, thin-walled, rarely branched, 4–6 μm diam; hyphal cells short and infated, pale brown in KOH, cyanophilous, inamyloid. Cystidia absent. Basidia 10–55 μm long and 4–9 μm diam at apex, 3–6 μm at base, with a clamp connection at base, utriform, not stalked, sinuous, rarely with transverse septa, pale brown in KOH and in distilled water, 4-sterigmate; sterigmata 6–8.5 μm long and 1.5–2.5 μm diam at base. Basidiospores thick-walled, (8–)8.5–9.5(–11)×(7.5– )8–9(–10.5) μm, L=8.75 μm, W=8.23 μm, Q=1.05–1.09 (n = 60/2), globose to subglobose in frontal and lateral views, echinulate, pale brown in KOH and in distilled water, cyanophilous, inamyloid; echinuli usually isolated, sometimes grouped in 2 or more, up to 2 μm long.
Material examined – CHINA, Jilin Province, Changbaishan Nature Reserve, on fallen angiosperm branch, 7 August 2016, Yuan 11305 (IFP 019285, holotype), Yuan 11316 (IFP 019286).
GenBank numbers – ITS: MK211716, MK211717; LSU: MK446372, MK446373.
Notes – Tomentella stipitata is similar to T. fuscopelliculosa by basidiocarps adherent to the substrate, a farinaceous sterile margin, short and inflated subhymenial hyphal cells, utriform basidia, thick-walled basidiospores and the absence of rhizomorphs and cystidia. However, T. stipitata differs from T. fuscopelliculosa by having mucedinoid basidiocarps and subglobose to bi- or tri-lobed basidiospores. T. pertenuis resembles T. fuscopelliculosa by basidiocarps adherent to the substrate with a farinaceous sterile margin, utriform basidia, the absence of rhizomorphs and cystidia, and thick-walled, globose to subglobose basidiospores. But, it is differentiated by yellowish brown basidiocarps, slightly thick-walled subhymenial hyphae, and more or less uniform subhymenial hyphal cells.
Figure 1 – A basidiocarp of Tomentella fuscopelliculosa (IFP 019285, holotype)
Figure 2 – SEM of basidiospores of Tomentella fuscopelliculosa (IFP 019285, holotype)
Figure 3 – Microscopic structures of Tomentella fuscogranulosa (IFP 019283, holotype). a Hyphae from a rhizomorph. b Section through a basidiocarp. c Basidiospores in frontal view. d Basidiospores in lateral view