Dermoloma simile Adamčík & Jančovič. sp. nov.

Figs 48 c, d, 50

Etymology.

Similar to the generic type, Dermoloma cuneifolium.

Holotype.

United Kingdom • Wales, Pembrokeshire, Upton Castle, coord. 51°42'22"N, 04°51'57"E, terrestrial in lawn, 26 Oct 2014, D. Harries (SAV F-4421).

Diagnosis.

European species; basidiomata small to medium-sized; pilei 8–22 mm in diameter, with margins indistinctly striate when wet; stipes and lamellae predominantly grayish-ochraceous or grayish brown; spores inamyloid, on average up to 3.6 µm wide and / or Q> 1.4; caulocystidia 3–6 µm wide.

Pileus (6 –) 8–22 (– 28) mm; convex, expanding to plane, sometimes indistinctly umbonate, sometimes lobate; margin not striate, indistinctly translucently striate to half of radius when wet; surface smooth near margin, rough, radially rugulose, sometimes wrinkled or veined near center, weakly hygrophanous; color when young near margin grayish brown (6 E 3,7E 3) to brown (7 E 4), near center dark brown (7 F 4) to black, when mature near margin brown (5 E 4,6E 4,6E 5), grayish brown (5 D 3,6E 3), light brown (6 D 5), brownish gray (6 C 2), when dry grayish brown (5 D 3, 6 D 3), brownish ochraceous (5 C 3, 6 C 3), ochraceous-gray (5 B 2, 6 B 2), near center dark brown (6 F 3, 6 F 4, 6 F 5) to almost black, brown (6 E 46 E 5), grayish brown (6 D 3,6E 3), when dry sometimes paler brown (5 E 4) to brownish ochraceous (6 C 3). Stipe (15 –) 21–39 (– 52) × 1–4 mm; cylindrical, narrowed towards the base, flexuous; surface finely longitudinally striate, when young pruinose along all length, when mature towards the base finely fibrillose or silky and shiny; color grayish ochraceous (5 B 3), ochraceous-gray (5 B 2) to almost white, near the base concolorous or darker, especially with age, brownish ochraceous (5 C 3, 6 C 3, 7 C 3), grayish brown (5 D 3, 6 D 3) or brownish gray (6 C 2). Lamellae L = (20 –) 23–38, l = 0–3; 2–5.5 mm wide; adnate-emarginate and decurrent with tooth; color ochraceous-gray (5 B 2, 6 B 2) to almost white, brownish gray (5 C 2, 6 C 2, 7 C 2), grayish brown (5 D 3), grayish ochraceous (5 B 3); edges entire. Context fragile; odor farinaceous.

Spores (3.9 –) 4.7–5.1 – 5.4 (– 6.1) × (2.9 –) 3.3–3.5 – 3.8 (– 4.6) μm; ellipsoid to narrowly ellipsoid, Q = (1.15 –) 1.31–1.43 – 1.55 (– 1.91); walls inamyloid, sometimes thick-walled and dextrinoid; hilar appendage ca. 0.5–1.5 μm long. Basidia (17 –) 22–25.4 – 28.6 (– 34) × (4.5 –) 5.5–6.1 – 7 (– 8.5) μm; clavate; with 4 sterigmata. Basidioles first cylindrical, then clavate, ca. 3–6.5 μm wide. Marginal cells (10 –) 11–14.5 – 18 (– 24.5) × (3.5 –) 4–4.9 – 6 (– 6.5) μm; not well-differentiated, clavate, rarely cylindrical or ellipsoid, often flexuous. Pileipellis 65–105 μm deep; suprapellis 45–55 μm deep, usually of two or three layers of inflated, densely arranged cells; subpellis well-differentiated, 20–50 μm deep, of densely packed, irregularly oriented, intricate, 3–10 (– 18) μm wide hyphae, gradually passing to horizontally oriented hyphae in trama; hyphal terminations with brownish parietal pigments, in subpellis locally also with dark brown incrusted pigments, walls thickened up to 1 μm especially in subpellis. Terminal cells near pileus margin (22.5 –) 31.5–41.3 – 51 (– 75) × (7 –) 14.5–19.7 – 25 (– 36) μm; sphaeropedunculate, obpyriform or clavate; subterminal cells clavate or fusiform and usually equally wide, sometimes also narrower and almost cylindrical, usually unbranched. Terminal cells near pileus center (18.5 –) 31–40.8 – 51 (– 70) × (7 –) 12–18.6 – 25 (– 36) μm; similar to cells near margin; subterminal cells narrower and subcylindrical, more frequently with dark brown incrustations. Caulocystidia (16.5 –) 23–32.6 – 41 (– 59.5) × (2.5 –) 3–4.6 – 6 (– 10) μm; clavate or cylindrical, usually not or only slightly flexuous, often clustered in repent or ascending fascicules, sometimes individual and repent; usually slightly thickened up to 0.5 μm, often with crystalline or granulose yellow incrustations. Clamp connections present.

Distribution and ecology.

Widely distributed, mainly in temperate regions, but also found in boreal-montane sites. Known from Austria, Croatia, Finland, Germany, Slovakia and United Kingdom; in semi-natural grasslands, once in a woodland meadow, and once in a rich deciduous forest; probably preferring calcareous soil.

Additional material studied.

Austria • Steiermark, Graz-Umgebung, Frohnleiten, Rabenstein, elev. 466 m, coord. 47°14'59"N, 15°18'25"E, on soil among mosses and grass, 2 Oct 2021, G. Friebes GF 20210511 (SAV F-23431). Croatia • podr. Hunjka / Rauchova lugarnica, ca. 400 m NW / N-NW, pl. Medvednica, coord. 45°55'03"N, 15°58'13"E, pasture near forest of Fagus sylvatica, Pinus sylvestris, Betula pendula and Populus tremula, 27 Sep 2009, A. Mešić (CNF 1/5620). Finland • Etelä-Häme, Nokia, Sarpatti, Maatialanharju, coord. 61°29'02"N, 23°33'18"E, on dry meadow under Pinus sp., Betula sp., Sorbus sp., 29 Sep 2004, U. Salo and P. Salo FISAP 656-13 (H 6016609). Germany • Baden-Württemberg, Justingen, Schachenheide, coord. 48°24'35"N, 09°40'25"E, terrestrial in semi-natural grassland, 2 Oct 2021, M. Caboň (SAV F-20858); • ibid., 3 Oct 2021, S. Adamčík (SAV F-20906). Slovakia • Javorie Mts., Slatinské Lazy, Jombíkovci, meadow near Matúšov hájik cottage, elev. 460 m, coord. 48°29'47"N, 19°19'08"E, terrestrial, 22 Oct 2020, M. Caboň (SAV F-20758); • ibid., 22 Oct 2020, leg. M. Caboň (SAV F-20759); • Kremnické vrchy Mts., pasture 0.5 km W of Tajov, elev. 600 m, coord. 48°44'54"N, 19°03'31"E, terrestrial, 25 Oct 2020, M. Caboň (SAV F-20836); • Laborecká vrchovina Mts., 1.5 km NNE of Svetlice, elev. 390 m, coord. 49°11'03"N, 22°02'38"E, terrestrial on pasture, 21 Sep 2006, S. Adamčík (SAV F-4140); • ibid., 23 Oct 2007, S. Adamčík (SAV F-4141); • ibid., 23 Oct 2007, S. Adamčík (SAV F-4152); • Poloniny Mts., 4 km N of Stakčín, pastures above the water reservoir Starina, elev. 380–420 m, coord. 49°02'43"N, 22°14'56"E, terrestrial, 25 Sep 2017, M. Caboň (SAV F-20228); • Zvolenská kotlina Basin, pasture E of Bečov, elev. 400–450 m, coord. 48°38'48"N, 19°14'49"E, terrestrial, 17 Sep 2020, S. Adamčík (SAV F-20661). United Kingdom • England, Shropshire, Shrewsbury – cemetery, coord. 52°41'46"N, 02°45'32"E, terrestrial in lawn, 21 Oct 2014, S. Adamčík (SAV F-4359); • Wales, Pembrokeshire, Upton Castle, coord. 51°42'22"N, 04°51'57"E, terrestrial in lawn, 26 Oct 2014, D. Harries (SAV F-4414).

Notes.

Dermoloma simile is a member of D. subgenus Dermoloma, section Dermoloma. It is sister to D. carpathicum (Fig. 2) which is also the most similar species. For the morphological circumscription of D. simile, see the notes under D. carpathicum. The species was included in the phylogenetic study by Sánchez-García et al. (2021) and labeled as “ Dermoloma sp. 1 ” and “ Dermoloma sp. 2 ”. Our multilocus phylogeny did not support two species and the support in the previous study was probably based on different ITS sequence variants of D. simile.