Pluteus anatolicus Kaygusuz, Knudsen, Menolli & Türkekul, 2021

Kaygusuz, Oguzhan, Knudsen, Henning, Jr, Nelson Menolli & Türkekul, Ibrahim, 2021, Pluteus anatolicus (Pluteaceae, Agaricales): a new species of Pluteus sect. Celluloderma from Turkey based on both morphological and molecular evidence, Phytotaxa 482 (3), pp. 240-250 : 243-245

Pluteus anatolicus Kaygusuz, Knudsen, Menolli & Türkekul , sp. nov. ( Figs. 2–4 )

MycoBank: —MB835683

Holotype: — TURKEY. Artvin Province, Hopa district, around Çavuşlu town , under Fagus orientalis , at 41°23′20.7″N, 41°30′12.8″E, alt. 670 m, 28 September 2015, O. Kaygusuz, OKA-TR202 ( GUL); GenBank: MT 523034 .

Diagnosis:— Pluteus anatolicus is morphologically close to the European species P. multiformis but distinguished by the combination of a small-sized basidioma, pileus with cracking surface depressed at the center, broadly ellipsoid to ellipsoid basidiospores, presence of cheilocystidia and pleurocystidia, a pileipellis with pyriform, limoniform or spheropedunculate cells, which are predominantly broadly mucronate at apex and with long pedicel, and absence of caulocystidia.

Etymology: —From anatolicus (Latin) , referring to the region of Anatolia in Turkey, from where it is described.

Description:—Pileus 7–10 mm, at first hemispherical, then plano-concave to concave, slightly depressed at center, not umbonate, surface smooth or sometimes irregularly wrinkled at center, occasionally cracked and revealing the whitish flesh, not hygrophanous, persistently light to pale brown overall, slightly darker at center. Lamellae free, moderately crowded, up to 1 mm broad, thin, whitish, edge concolorous. Stipe 30–35 × 1–1.5 mm, cylindrical, slender, mostly equal but subbulbous or slightly swollen at the base, finely pubescent, white to whitish cream except for the pale brown base. Context white. Smell and taste not distinctive.

Basidiospores (5.5‒)5.7‒7.2(‒8.1) × (4.3‒)4.5‒5.3(‒6.0) μm, L m × W m = 6.4 × 4.9 μm, Q = (1.1‒)1.2‒1.4(‒ 1.7) Q m = 1.3 broadly ellipsoid to ellipsoid, rarely subglobose or elongate, guttulate, hyaline, smooth, thick-walled, inamyloid. Basidia (20‒)23‒28(‒29) × 6.9‒8.4(‒8.6) μm, clavate, four‒spored, hyaline, with granular contents, thin-walled. Basidioles 10.5‒21 × 3.5‒5.8 μm, clavate. Pleurocystidia (35‒)37‒67(‒78) × (7.5‒)9.5‒19.0(‒28) μm, scattered, scarce to moderately abundant, narrowly utriform to narrowly fusiform or fusiform, with rounded to obtuse or subcapitate apex 9–20 μm, sometimes with up to 20 μm long pedicel, rarely utriform or lageniform, thin-walled, hyaline or sometimes with evenly dissolved brown intracellular pigment. Lamellar margin sterile. Cheilocystidia (13.5‒)16.5‒53(‒65) × (6.5‒)8.0‒22.5(‒34) μm, abundant, most frequently narrowly clavate to clavate, a few subutriform or broadly fusiform, thin-walled, hyaline. Pileipellis an euhymeniderm or as a transition between a hymeniderm and an epithelium, composed of pedicellate, pyriform to spheropedunculate or clavate elements, (24–)33‒65(–80) × (13–)18–30(–41) μm, with broadly mucronate apex up to 10 μm long, generally with up to 30 μm long pedicel, thin-walled, with evenly dissolved yellow-brown intracellular pigment in KOH. Caulocystidia not observed. Stipitipellis a cutis of 5.0–12.0(–15.0) μm wide hyphae, made up of cylindrical thin-walled, colorless and hyaline. Clamp connections absent in all parts examined.

Habit, habitat and distribution: —Solitary, between late September and early October, generally present at elev. 650–700 m, under Fagus orientalis , without visible connection to wood, on moist to wet acidic non-calcareous sandyloamy soils, which are rich in organic matter. Currently known only from the Black Sea region of Turkey (Artvin Province).

Additional specimen examined: — TURKEY. Artvin Province: Hopa district, around Çavuşlu town , under Fagus orientalis , at 41°23′20.9″N, 41°30′12.2″E, alt. 680 m, 01 October 2015, O . Kaygusuz , OKA-TR203 ( GUL); GenBank: MT 523035 .

Figures

FIGURE 2. Fresh basidioma of Pluteus anatolicus (OKA-TR202; holotype) on natural habitat. a, c. Basidioma in side view. b. Close-up of the pileus surface. d. Lamellae view. Scale bars: a, c = 10 mm; b, d = 5 mm.

FIGURE 3. Microcharacters of Pluteus anatolicus (OKA-TR202; holotype): a. Basidiospores. b. Basidia and basidioles. c. Pleurocystidia. Scale bars: a = 5 μm; b, c = 10 μm.

FIGURE 4. Microcharacters of Pluteus anatolicus (OKA-TR202; holotype): a. Cheilocystidia. b. Pileipellis elements. Scale bars = 10 μm.