Neodermoloma campestre Sánchez-García, Matheny & Adamčík, 2025

Adamčíková, Katarína, Kiran, Munazza, Caboň, Miroslav, Matheny, Brandon P., Sánchez-García, Marisol, Arnolds, Eef, Caboňová, Michaela, Corriol, Gilles, Dima, Bálint, Friebes, Gernot, Griffith, Gareth W., Grootmyers, Django, Harries, David, Karich, Alexander, Mešić, Armin, Mihaljevič, Martin, Moreau, Pierre-Arthur, Pošta, Ana, Shapkin, Vasilii, Tkalčec, Zdenko, Vizzini, Alfredo, Vondrovicová, Lenka, Adamčík, Slavomir & Jančovičová, Soňa, 2025, A phylogenetic and morphological study of the genus Dermoloma (Agaricales, Tricholomataceae) in Europe and North America exposes inefficiency of opportunistic species descriptions, IMA Fungus 16, pp. e 157337-e 157337 : e157337-

Neodermoloma campestre Sánchez-García, Matheny & Adamčík sp. nov.

Figs 51 b , 54

Etymology.

In reference to occurrences in grassy lawns.

Holotype.

USA • Tennessee, Maynardville, Union Co., Big Ridge State Park , on soil in a lawn, 11 Aug 2018, P. B. Matheny & S. R. Warwick PBM 4177 ( TENN-F-074505 ).

Diagnosis.

North American species; basidiomata relatively large, pale colored; color prevailingly ochraceous-gray to grayish brown; pilei 20–45 mm in diameter; stipes 4–11 mm wide; lamellae 42–48 near the stipe; pileipellis with similar cellular structure as found in Dermoloma but with terminal elements mainly <12 µm wide.

Pileus 20–45 mm; obtusely conical, campanulate, expanding to plane, at times with a low obtuse umbo; margin decurved to straight, not striate; surface smooth, near center rough to bumpy, dry, dull, not noticeably hygrophanous; color near margin ochraceous-gray (6 B 2) or light grayish drab, towards center brown (6 E 4), often with a bluish-gray tone. Stipe 40–65 × 4–11 mm; cylindrical and slightly tapering towards the base, equal, not bulbous, solid or stuffed; surface dry, veil absent, finely fibrillose, easily splitting with age; color streaked gray-drab with white areas, overall light brownish gray (5 D 2) to grayish brown (5 E 3), whitish at extreme point of attachment. Lamellae L = 42–48, l = 1–3; up to 11 mm wide; sinuate to adnate; color yellowish white ochraceous-gray (6 B 2) to brown (6 E 4); edges entire, concolorous. Context compact, flesh grayish, not changing color when bruised; odor unpleasant like a dirty dish rag, taste farinaceous. Negative reaction with KOH and PDAB.

Spores (4.4 –) 4.7–5.2 – 5.7 (– 6.8) × (3.5 –) 3.8–4 – 4.3 (– 4.7) μm; broadly ellipsoid to ellipsoid, Q = (1.15 –) 1.21–1.30 – 1.38 (– 1.58); walls amyloid; hilar appendage 0.7–1 μm long. Basidia (20 –) 22.5–27.1 – 31.5 (– 39) × (5 –) 5.5–6.4 – 7 (– 8) μm; clavate; with 4 sterigmata, occasionally with 2 sterigmata, rarely 1 or 3 sterigmata. Basidioles first cylindrical, then clavate, ca. 3–7 μm wide. Marginal cells (13 –) 15.5–18.6 – 21.5 (– 25) × (2.5 –) 3.5–4.4 – 5.5 (– 7) μm; not well-differentiated and similar to Basidioles but narrower, mainly cylindrical or clavate, apically obtuse, often slightly flexuous. Pileipellis 50–77 μm deep; suprapellis 47–57 μm deep, usually of multiple layers of inflated and densely arranged but near surface loose cells; subpellis not well defined, 14–23 μm deep, of densely packed, horizontally oriented, intricate, narrow, 3–6 μm wide hyphae, sharply delimited from horizontally oriented and intricate hyphae in trama; hyphal terminations with brownish yellow parietal, in subpellis also incrusted but not darker pigments, walls thickened up to 0.5 μm. Terminal cells near pileus margin (12 –) 17–24.8 – 32.5 (– 45) × (6 –) 9–10.9 – 12.5 (– 15.5) μm; usually obpyriform, occasionally clavate or ellipsoid, rarely sphaeropedunculate; subterminal cells branched or not, ventricose or cylindrical, occasionally inflated, often lobate or with lateral swellings. Terminal cells near pileus center (11 –) 15–23.1 – 31.5 (– 47) × (4.5 –) 7.5–9.2 – 11 (– 13) μm; clavate, obpyriform or sphaeropedunculate, occasionally fusiform; subterminal cells mainly cylindrical or narrowly clavate, occasionally ventricose. Caulocystidia (21 –) 26.5–37.4 – 48.5 (– 72) × (4 –) 4.5–7.2 – 10 (– 14) μm; narrowly clavate or subcylindrical, occasionally slightly flexuous, repent or with ascending tips, dispersed, individual or in small clusters; thin-walled, with pale brownish yellow parietal pigments, on subterminal cells also incrusted pigments. Clamp connections present.

Additional material studied.

USA • South Carolina, Weinnsboro , on soil in a lawn, 27 Aug 1966, C. Lyles RHP 29387 ( TENN-F-029387 , as Dermoloma hymenocephalum ) ; • Tennessee, Maynardville, Union Co., Big Ridge State Park , on soil in a lawn, 26 Sep 2011, B. Williams BW 8 ( TENN-F-066899 ) .

Notes.

The North American species N. campestre is the only known member of the genus. It is characterized by a pileipellis structure similar to that seen in Dermoloma , but with terminal cells that are significantly narrower (up to 12 μm) than those observed in any species of the latter genus. The relatively large and robust, pale colored basidiomata strikingly resemble those of D. hygrophorus , which differs by more distant lamellae (L <30). The species was included in the phylogenetic study by Sánchez-García and Matheny (2017) and Sánchez-García et al. (2021) as “ Dermoloma sp. ”.

Figures

Figure 51. Basidiomata of Dermoloma in field appearance. a Dermoloma vellingae (TENN-F- 065324, holotype), photo E. C. Vellinga; b Neodermoloma campestre (TENN-F- 074505, holotype), photo P. B. Matheny. Scale bar: 10 mm.

Figure 54. Neodermoloma campestre (TENN-F- 066899), microscopic elements. a Spores; b caulocystidia; c basidia and basidioles; d marginal cells; e pileipellis elements near the pileus margin; f pileipellis elements near the pileus center. Scale bar: 5 µm for spores and 10 µm for other elements.