Lyomyces boquetensis Yurchenko & Riebesehl 2024, sp. nov.
Creators: name: Yurchenko, Eugene
name: Langer, Ewald
name: Riebesehl, Janett
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Corticiales
Hymenochaetales
Lyomyces
Lyomyces boquetensis

description: Lyomyces boquetensis Yurchenko & Riebesehl sp. nov.
Figs 3 A, B, 4, 16 A, B
Type.
Panama • Chiriquí Province: W of Boquete town, Bajo Boquete community, 08 ° 46.58 ' N, 082 ° 28.17 ' W, 1450 m a. s. l., evergreen montane tropical forest, bottom of canyon with a rivulet, on fallen corticated twig of angiosperm, 27 Jul 2019, E. Yurchenko EYu 190727-12 (holotype: BLS M-5238; isotype: CFMR). GenBank: ITS = PP 471797; 28 S = PP 471818.
Etymology.
boquetensis = refers to Boquete, the town near the type locality.
Description.
Basidiomata effused, 1.5–3 and more cm in extent, soft-membranaceous to membranaceous, from fine flocculose or granulose and discontinuous when young to continuous, 20–60 μm thick between warts. Hymenial surface white or dirty whitish, smooth to minutely warted; warts up to 3–7 / mm, 15–60 μm high. Margin concolourous, appressed mould-like or diffuse, about 0.5 mm wide. Hyphal system monomitic, hyphae clamped at all septa, smooth (in KOH) or slightly encrusted (in Mz). Subiculum of loose texture; subicular hyphae moderately branched, 2–4 μm wide, thin- to somewhat thick-walled (walls up to 0.7 μm thick). Subhymenium thin; subhymenial hyphae richly branched, 2–3.7 μm wide, thin-walled. Cystidia thin-walled, colourless, smooth to heavily encrusted, of four types: 1) capitate scarce to common, 15–30 × 3.5–5 μm; 2) capitulate not frequent, 23–35 × 3–4.5 μm; 3) cylindrical and subcylindrical scattered, 20–28 × 3–4.3 μm; 4) fusoid rare, 25–35 × 4.5–5 μm. Incrustation on cystidia and basidioles partly dissolving in KOH. Basidioles short cylindrical to clavate, 10–13 × (3 –) 3.5–4.7 μm, smooth or slightly encrusted. Basidia cylindrical-utriform, 10.5–15.5 × 3.2–4 μm, smooth or slightly encrusted; sterigmata four, reaching 2.5–3 × 0.3–0.5 μm. Basidiospores ellipsoid to narrowly ellipsoid, 4–5 (– 5.5) × 2.7–3 (– 3.5) μm (L = 5.1 μm, W = 3.3 μm), thin-walled, smooth, colourless, some with a drop inside, Mz –, acyanophilous; apiculus minute, short.
Distribution.
So far, only known from Panama.
Ecology.
The species grows on small-sized dead corticated wood in tropical evergreen forests.
Notes.
The main diagnostic features of this species are a minutely warted hymenial surface, thickened walls in the subicular hyphae, the presence of smooth to heavily encrusted capitate and cylindrical cystidia, and thin-walled, narrowly ellipsoid basidiospores. This species is most morphologically similar to L. sambuci, L. densiusculus, and L. denudatus. It differs from L. sambuci s. str. by the presence of heavily encrusted capitulate cystidia and thin-walled basidiospores. The presence of richly encrusted capitulate cystidia and smaller basidiospores are the characteristics which separate L. boquetensis from L. densiusculus. Warted hymenial surface, cylindrical cystidia, and smaller basidiospores differentiate the new species from L. denudatus. The new species differs from a phylogenetically close L. lancangjiangensis by shorter and narrower basidiospores.
description: Published as part of 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, pp. 131-169 in MycoKeys 109 on pages 131-169, DOI: 10.3897/mycokeys.109.127606