Lyomyces sceptrifer Yurchenko & Langer, 2024

Yurchenko, Eugene, Langer, Ewald & Riebesehl, Janett, 2024, A high species diversity of Lyomyces (Basidiomycota, Hymenochaetales) in Central and South America, revealed after morphological and molecular analysis, MycoKeys 109, pp. 131-169 : 131-169

Lyomyces sceptrifer Yurchenko & Langer sp. nov.

Figs 8 G , 14

Type.

Ecuador • Zamora Chinchipe Province: 17 km NW of Zamora, in the vicinity of Estación Científica San Francisco, near the San Francisco River, Permanent sample plot No. 1 , 03 ° 58.33 ' S, 079 ° 04.67 ' W, about 1850 m a. s. l., on a dead bamboo stem, 5 Mar 2002, E. Langer 1 / 661 (holotype: KAS-Ec 661-2002 ; isotype: CFMR). GenBank: ITS = PP 471811; 28 S = PP 471827 .

Etymology.

sceptrifer (Lat.) = bearing sceptrum, referring to the shape of cystidia with a prominent capitulum and widened lower half.

Description.

Basidiomata effused, 5 and more cm in extent, 40–70 μm thick, loose- or soft- membranaceous. Hymenial surface cream-coloured, even, but under a lens very minutely porulose. Margin concolourous, from abrupt to thinning out and diffuse, up to 0.5 mm wide. Hyphal system monomitic, hyphae clamped at all septa, colourless, smooth. Subicular hyphae moderately branched, (1.5 –) 2–3.3 μm wide, thin- to slightly thick-walled. Subhymenial hyphae richly branched, 1.5–3.5 μm wide, thin-walled. Cystidia of three main types: 1) capitate numerous, 22–33 × 3.5–6, with long narrow neck and widened base, apically naked, seldom bearing a cap of transparent matter, hardly preserved in preparations; 2) cylindrical and irregularly-cylindrical scarce, (20 –) 30–65 × 3–7 μm; 3) clavate scarce, 30–35 × 8 μm. Basidioles clavate to utriform, (7.5 –) 9–16 × 3.5–4.7 μm. Basidia utriform, 16–18.5 × 4–5 μm, sterigmata four, 4–5.5 × 0.7–1 μm. Basidiospores ellipsoid, 4.3–4.8 (– 5) × 2.7–3 (– 3.5) μm (L = 4.7 μm, W = 2.9 μm), Q = 1.4–1.7, smooth, colourless, with thin or faintly thickened wall, Mz –, acyanophilous; apiculus well-pronounced.

Distribution.

So far, known from the Andes Mountains in southern Ecuador.

Ecology.

The species grows on dead lignified stems in evergreen tropical montane forests.

Notes.

The main diagnostic features of this species are an even hymenial surface, smooth, slightly thick-walled subicular hyphae, smooth, capitate cystidia with long narrow neck, and ellipsoid basidiospores with thin- to faintly thickened walls and well-pronounced apiculus. The species differs from close taxon L. sambuci by the absence of crystalline incrustations on capitate cystidia and the presence of scattered, fairly large subcylindrical cystidia.

Figures

Figure 8. Macromorphology of Lyomyces species A L. oleifer, holotype (KAS-Ec 47-2001) B L. orarius, holotype (BLS M- 2995) C L. pantropicus, holotype (BLS M- 2679) D L. pantropicus, BLS M- 3545 E L. parvus, holotype (KAS-GEL 1599) F L. parvus, BLS M- 2990 G L. sceptrifer, holotype (KAS-Ec 661-2002) H L. subcylindricus, holotype (BLS M- 2668). Scale bars: 1 mm.

Figure 14. Micromorphology of Lyomyces sceptrifer (holotype, KAS-Ec 661-2002) A vertical section through basidioma B subicular hyphae C capitate cystidia D Incrustations and attached basidiospores on cystidia E Irregularly cylindrical cystidia F basidioles G basidia H basidiospores. Scale bars: 10 μm (A – G); 5 μm (H).