Entoloma chamaemori Noordel., Weholt, Eidissen & Lorås, 2017

Noordeloos, Machiel Evert, Dima, Bálint, Weholt, Øyvind, Eidissen, Siw Elin, Lorås, Jostein & Brandrud, Tor Erik, 2017, Entoloma chamaemori (Entolomataceae, Basidiomycota) - a new boreal species, with isolated phylogenetic position, Phytotaxa 298 (3), pp. 289-295 : 291

Entoloma chamaemori Noordel., Weholt, Eidissen & Lorås sp. nov. Figs 1–3 .

MycoBank: MB818574

Diagnosis:—Habit mycenoid with 25–40 mm wide, conico-convex, expanding pileus, reddish brown with darker centre, glabrous, smooth. Lamellae distant to moderately crowded, narrowly adnate-emarginate to (almost) free, greyish white with pinkish tinge, with concolorous edge. Stipe 50–70 × 3–5 mm, greyish white, apex pruinose, silvery striate lengthwise. Smell farinaceous. Spores 6.0–8.0(–8.5) × 5.5–7.0(–7.5) μm, isodiametrical to subisodiametrical, with 6–8 rather weak angles, thin-walled. Basidia 4-spored, clamped. Pileipellis a differentiated (ixo-) cutis, with scattered clavate to cystidiform terminal elements, 20–35 × 4–12 μm and brown intracellular pigment. Clamps present.

Holotype:— NORWAY. Nordland, Grane, Holmvassdalen Nature Reserve , UTM 33 W E 0418334 N 7236942 , 10 August 2014, S. E. Eidissen & J. Lorås, JL 69-14 (holotype, O!). GenBank: KX928955.

Etymology:—Named after Rubus chamaemorus (a low herbaceous member of the genus Rubus ), among which the species was found.

Description:— Pileus 25–40 mm broad, conico-convex, slightly expanding with age to convex, obtuse or umbonate, with deflexed margin, translucently striate up to half the radius, brown with a reddish tinge, darker blackish brown at centre, distinctly paler at outermost margin, glabrous, smooth. Further pileus surface structures are not noted, but apparently slightly sticky-viscid when moist. Lamellae distant to moderately crowded, free or narrowly adnate–emarginate, ventricose, up to 3 mm broad, greyish white, darker pinkish grey-brown with age, with entire, concolorous edge. Stipe 50–70 × 3–5 mm, cylindrical, greyish white, paler, almost white at base, longitudinally silvery fibrillose-twisted, apex white pruinose. Smell farinaceous. Spores 6.0–8.0(–8.5) × 5.5–7.0(–7.5) μm, average 7.0 × 6.0 μm, Q = 1.0–1.2, Qav = 1.05, isodiametrical to subisodiametrical, with 6–8 rather weak angles, thin-walled. Basidia 18–24(–32) × 5–8(–10) μm, 4-spored, clamped. Cystidia absent. Hymenophoral trama regular to subregular, made up of cylindrical to slightly inflated hyphae, 5–12 μm wide. Brilliant granules not observed. Pileipellis a differentiated (ixo-) cutis, suprapellis an entangled layer of cylindrical hyphae, 2–5 μm wide with scattered clavate to cystidiform terminal elements, 20–35 × 4–12 μm. Pigment abundant, brown, intracellular, often in form of tightly packed brown granules, but also diffusely spread in content of elements; no incrusting pigments observed. Stipitipellis a loose cutis of cylindrical hyphae, 2–7 μm wide. Clamp-connections abundant in hymenium, scattered to abundant in context and pileipellis.

Habitat and distribution:—Among Sphagnum papillosum and S. tenellum in open, sub-exposed, oligotrophic bog with predominantly Rubus chamaemorus , accompanied by Drosera rotundifolia , Eriophorum angustifolium , Andromeda polifolia , some low bushes of Betula nana , and Betula pubescens , and small Pinus sylvestris . Soil pH about 4.5. Two collections were found, approx. 3 meters apart.

Additional specimens studied:— NORWAY. Nordland, Grane, Holmvassdalen Nature Reserve, UTM 33W E 0418334 N 7236942, 10 August 2014, S. E. Eidissen & J. Lorås, JL70- 14 (O!). GenBank: KX928956.

Figures

FIGURE 1. Maximum likelihood phylogeny (ITS) of selected members of the genus Entoloma inferred from RAxML analysis. Newly generated sequences are highlighted in bold. Sequence origins (GenBank) as well as voucher numbers (where available) are given. RAxML bootstrap supports values (>70%) and Bayesian posterior probabilities (>0.90) are indicated on the branches at nodes (ML/PP). The bar indicates 0.05 expected change per site per branch.

FIGURE 2. Entoloma chamaemori. Holotype in situ. Photo Jostein Lorås

FIGURE 3. Entoloma chamaemori. Habitat in Holmvassdalen Nature Reserve. Photo Jostein Lorås.