Xylodon crystalliger Viner

Viner, Ilya, Spirin, Viacheslav, Zibarova, Lucie & Larsson, Karl-Henrik, 2018, Additions to the taxonomy of Lagarobasidium and Xylodon (Hymenochaetales, Basidiomycota), MycoKeys 41, pp. 65-90 : 70-72

Xylodon crystalliger Viner sp. nov. Figure 4

Type.

RUSSIA. Primorie: Khasan Dist., Kedrovaya Pad Nat. Res., on angiosperm wood, 25 Jul 2016, I.Viner KUN 2312 (H) - ITS sequence, GenBank MH324477.

Etymology.

Crystalliger (lat., adj.) - bearing crystals.

Description.

Basidiocarp effused, soft membranaceous, up to 6 cm in widest dimension. Sterile margin poorly defined, up to 0.3 mm wide. Hymenial surface white, minutely odontioid, i.e. covered by small peg-like hyphal projections up to 60-100 μm high, 60-75 μm broad at base, 10-15 per mm, with flattened fimbriate apices. Surface between projections porulose-reticulate. Hyphal structure monomitic, hyphae clamped, faintly cyanophilous. Subicular hyphae densely interwoven, often with thickened walls, 3.2-4.4 μm in diam. (n=20/2), smooth or sparsely encrusted. Tramal hyphae subparallel, thin- to clearly thick-walled, sparsely encrusted, subhymenial hyphae densely arranged, sometimes short-celled, 2.5-3.2 μm in diam. (n=20/2), sparsely encrusted. Hyphal ends at the top of projections often strongly encrusted. Cystidia of two types: a) sparsely encrusted hyphoid cystidia at the top of projections, 21.0 –29.0×2.9–4.1(– 4.4) μm (n=40/2), b) subcapitate or cylindrical cystidia, of subhymenial origin, rather variable in shape and size, (11.8 –)14.1–25.0(–28.0)×(2.6–)2.9–4.6(– 4.8) μm (n=40/2), often heavily encrusted and rarely with a stellate crystalline cap 3.5-4.5 μm in diam. Basidia suburniform, 4-spored, 13.4 –18.4(–19.0)×4.2– 4.7 μm (n=20/2), slightly thick-walled at the base. Basidiospores thin-walled, elliptical, occasionally with an oil-drop, (3.1 –)4.2–5.1(–5.9)×(2.4–)3.3– 4.2 μm (n=60/2), L=4.66, W=3.71, Q=1.26, slightly cyanophilous.

Distribution and ecology.

East Asia (Russian Far East), on decayed angiosperm logs.

Remarks.

The peg-like hymenial projections and cystidia with stellate caps are characteristic for X. crystalliger and make it reminiscent of Xylodon astrocystidiatus (Yurchenko & Sheng H. Wu) Riebesehl, Yurchenko & Langer. The latter species is known from Taiwan and differs from X. crystalliger by having longer basidiospores and presence of constricted and bladder-like hymenial cystidia.