Lyomyces oleifer 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 oleifer Yurchenko & Langer sp. nov.

Figs 8 A , 9

Type.

Ecuador • Zamora Chinchipe Province: 17 km NW of Zamora, in the vicinity of Estación Científica San Francisco, Cordillera Consuelo Mountain Range, Permanent sample plot No. 3 , 03 ° 58.70 ' S, 079 ° 04.43 ' W, about 2150 m a. s. l., on corticated parts of a dead still-attached twig 8–10 mm in diam., 28 Aug 2001, E. Langer 7 / 47 (holotype: KAS-Ec 47-2001 ; isotype: CFMR). GenBank: ITS = PP 471802 .

Etymology.

oleifer (Lat.) = bearing oil, due to numerous drops of oily substance visible in microscopic sections of basidiomata.

Description.

Basidiomata effused, adnate, membranaceous, 0.2–5 and more cm in extent, between aculei from minutely porulose to continuous, 60–125 μm thick, cracking with age. Hymenial surface odontoid, cream-coloured or yellowish; aculei conical to subcylindrical, 5–7 / mm, 45–115 μm high, 20–65 μm in diam. Margin more or less concolourous, abrupt, narrowly mould-like (finely fimbriate) or thinning out, 0.2–0.5 mm wide. Hyphal system monomitic, hyphae clamped at all septa, colourless. Subicular hyphae 1.7–3.3 μm wide, thin- to somewhat thick-walled. Subhymenial hyphae densely agglutinated, 1.5–3.2 μm wide, thin-walled. Hymenial elements mostly indistinct due to the presence of oily matter in the hymenium. Cystidia smooth or encrusted, of several types: 1) capitulate or subcapitate common, 20–40 (– 45) × 2.5–4 μm, with apex 1.5–1.7 μm wide; 2) fusoid common, 25–30 (– 48) × 2.3–4.7 μm, apically blunt, occasionally acute; 3) cylindrical rare, 20–30 × 2.3–4.3 μm. Oily substance in the shape of drops, droplets, or amorphous masses present in hymenium or near cystidia in preparations (KOH). Basidioles clavate to subcylindrical, 13–30 × 3.5–5.5 μm. Basidia long-utriform, 20–25 × 4–4.5 μm; sterigmata four, 3.5–4 × 0.7–1 μm. Basidiospores narrowly ellipsoid to oblong, 5.5–6.5 (– 7) × 3.2–4 μm (in holotype L = 5.8 μm, W = 3.5 μm), Q = 1.6–1.7, slightly thick-walled, smooth, colourless, often with a drop inside, Mz –, acyanophilous; apiculus middle-sized.

Distribution.

Known from the Andes Mountains in southern Ecuador.

Ecology.

The species grows on dead twigs in evergreen tropical montane forests.

Additional specimens examined

(paratypes). Ecuador • Zamora Chinchipe Province: 17 km NW of Zamora, in the vicinity of Estación Científica San Francisco , between 1850 and 2450 m a. s. l., on dead corticated twigs 3–7 mm in diam., 3 Sep 2001, E. Langer 7 / 287 ( KAS-Ec287-2001 ; GenBank: ITS = PP 471803) ; • ibid., on a dead corticated branch, 8 Sep 2001, E. Langer 1 / 423 ( KAS-Ec423-2001 ; duplicate: CFMR; GenBank: ITS = PP 471804) .

Notes.

This new species differs from other species of Lyomyces by drops of oily substance, released in slides from all layers of basidioma. The size, shape, and refractive properties of the oily matter from the hymenium in this fungus depend on the age of basidioma. The new species differs from the most morphologically close L. crustosus by densely odontoid basidioma, numerous capitulate cystidia, tapering cystidia with mostly blunt apices, long-utriform basidia, and slightly thick-walled basidiospores. Besides the main types of cystidia described above, the intermediate forms between them are present in the specimens. In a paratype ( KAS-Ec 423-2001 ), the spores have L = 5.9 μm and W = 3.5 μm. For KAS-Ec 287-2001 and KAS-Ec 423-2001 , the features of white rot of the wood, associated with the basidiomata, were noted in the field.

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 9. Micromorphology of Lyomyces oleifer (holotype, KAS-Ec 47-2001) A, B vertical sections through basidioma C subicular hyphae D upper part of hymenium with oildrops E cystidia F basidioles G basidia H basidiospores. Scale bars: 100 μm (A); 20 μm (B); 10 μm (C – G); 5 μm (H).