Tomentella olivacea H.S. Yuan & Y.C. Dai 2020
Index Fungorum number: IF555705; Facesoffungi number: FoF 05636
Holotype: CHINA, Liaoning Province, Xifeng County, Binglashan National Forest Park, on rotten branch of Quercus, 2 August 2016, Yuan 11139 (IFP 019309, holotype); on rotten angiosperm branch, 1 August 2016, Yuan 11043 (IFP 019310), 2 August 2016, Yuan 11082, 11095, 11118 & 11141; on rotten angiosperm wood debris, Yuan 11103, 11108, 11113, 11120, 11121 & 11143.
Morphological description
Basidiocarps annual, resupinate, separable from the substrate, pelliculose, without odour or taste when fresh, 0.25–0.5 mm thick, continuous. Hymenophoral surface smooth to indistinctly granulose, olive brown (4F5–7) and turning darker than subiculum when dry. Sterile margin often determinate, byssoid, paler than hymenophore, almost pale brown. Subiculum mostly pale brown (5D6–8), Rhizomorphs present in subiculum, 10–20 μm diam; rhizomorphic surface more or less smooth; hyphae in rhizomorph monomitic, undifferentiated, of type B, compactly arranged and of uniform; single hyphae clamped, thick-walled, unbranched, 1–2 μm diam, yolk yellow in KOH, cyanophilous, inamyloid. Subicular hyphae monomitic; generative hyphae clamped, thin- to slightly thick-walled, rarely branched 3–4 μm diam, without encrustation, yellow in KOH, cyanophilous, inamyloid. Subhymenial hyphae clamped, thin-walled, frequently branched, 6–8 μm diam; hyphal cells more or less uniform, yellow in KOH, acyanophilous, inamyloid. Cystidia absent. Basidia 20–70 μm long and 5–7 μm diam at apex, 5–8 μm at base, with a clamp connection at base, clavate, stalked, not sinuous, without transverse septa, yellow in KOH, yellow in distilled water, 4-sterigmate; sterigmata 4–5 μm long and 1.5–2 μm diam at base. Basidiospores thick-walled, (6–)6.5– 7.9(–8.5) × (5–)5.5–6.8(–7) μm, L = 7.0 μm, W = 6.27 μm, Q = 1.08–1.17 (n = 60/2), irregularly globose or lobed in lateral and frontal views, echinulate, yolk yellow in KOH, yolk yellow in distilled water, cyanophilous, inamyloid; echinuli usually grouped in 2 or more, up to 0.5 μm long.
Habitat: On rotten branch of Quercus.
Distribution: In China.
GenBank Accession: ITS: KY686225, KY686224; LSU: MK446398, MK446397.
Notes: Tomentella olivascens (Berk. & M.A. Curtis) Bourdot & Galzin resembles T. olivacea in having olivaceous grey basidiocarps, thin- to slightly thick-walled subicular hyphae, thin-walled subhymenial hyphae and echinulate basidiospores of approximately the same size and shape. But, it differs by having basidiocarps adherent to the substrate and the absence of rhizomorphs in subiculum (Kõljalg 1996). T. ochraceo-olivacea Litsch. is similar to T. olivacea by having ochraceous to yellowish olivaceous baisidocarps, pale brown subiculum and irregular globose basidiospores of approximately the same size. However, it differs by its adherent, crustaceous to membranaceous basidiocarps and basidia frequently with transverse septa (Litschauer 1933).
Reference: Hai‑Sheng Yuan1,2· Xu Lu1,2 · Yu‑Cheng Dai3 ·
Basidiocarps of Tomentella olivacea (IFP 019309, holotype)
