Lepiota cremea O. Kaygusuz, 2022

Kaygusuz, Oğuzhan, 2022, Lepiota cremea, a novel species of Lepiota sect. Lepiota (Agaricaceae s. l., Agaricales) from Turkey, Phytotaxa 555 (4), pp. 291-300 : 294-296

Lepiota cremea O. Kaygusuz , sp. nov. ( Figs. 3‒5 )

MycoBank: —MB842020

Diagnosis: —Somewhat similar to Lepiota erminea but differing in pileus colour, which is pale beige, the absence of annulus on stipe, subcylindrical to fusiform basidiospores with higher Q m values, longer pileus covering elements, habitat in the Mediterranean coniferous forests, and distinct ITS sequence.

Type: — Turkey, Denizli Province: Çamlık district, around Çamlık Excursion Area , under Pinus nigra subsp. pallasiana (Lamb.) Holmboe , at 37°44′29.6″N, 29°5′20.4″E, alt. 430 m, 08 October 2016, O. Kaygusuz ( OKATR11019 , holotype, GenBank: ITS OL 630458 ) .

Etymology: —The epithet of “ cremea ” refers to the pale beige color of the pileus that characterizes this species.

Description:—Basidiomata small-sized, agaricoid. Pileus 20‒25 mm, at first hemispherical, then convex to planoconvex without umbo, slightly depressed at centre, smooth, silky, shiny, white except at centre where it is very pale ochre or pale yellowish brown tints, slightly fibrillose-scaly at centre, white and floccose along the margin. Lamellae moderately crowded (ca. 65–80, l = 1–2), free, thin, ventricose, white to cream. Stipe 22‒26 × 2.5‒3.0 mm, cylindrical to slightly broadened at base, in upper part pure white, smooth; fibrillose towards the base, whitish, particularly with pale yellowish brown tones near the base. Context in pileus and stipe white. Smell neutral or slightly unpleasant. Taste not distinctive.

Basidiospores (12.0‒)12.5‒16.5(‒17.0) × (5.4‒)5.8‒6.5(‒6.8) μm (n = 70 of 2 coll.), L m × W m = 14.2 × 6.1 μm, Q = (1.9‒)2.1‒2.5(‒2.7), Q m = 2.3, subcylindrical, fusiform, rarely oblong, with slight suprahilar depression above hilar appendage, with or without a large central (oil) drop, hyaline, dextrinoid, cyanophilic, not metachromatic; wall about 0.5‒0.9 μm thick. Basidia (33.0–)35.0–40.5(–50.0) × (9.2–)10.0–12.6(–14.0) μm (n = 60 of 2 coll.), clavate, 4-spored, sometimes 2-spored, hyaline, somewhat thick-walled, with cyanophilic content; sterigmata up to 5.0‒6.7 μm long. Lamella edge sterile. Cheilocystidia numerous and crowded, (11.5‒)14.0‒34.0(‒38.0) × (5.8‒)6.5‒10.5(‒11.0) μm (n = 70 of 2 coll.), mostly broadly to narrowly clavate or pyriform, sometimes cylindrical, smooth, thin to slightly thickwalled and hyaline. Pleurocystidia absent. Pileus covering a trichoderm composed of elongate, narrowly clavate to subcylindrical or subfusiform terminal elements (26.0‒)34.0‒158.0(‒185.0) × (3.5‒)6.5‒12.5(‒15.0) μm (n = 80 of 2 coll.), with rounded apex or narrow and tapering to apex, often with numerous short irregular excrescences, sometimes more or less erect, occasionally curved or twisted, densely aggregated and branching, frequently septate, hyaline, thick-walled; with short narrowly clavate elements under these elements, hyaline. Stipitipellis numerous, in clusters, (14.0‒)21.0‒55.5(‒80.0) × (6.0‒)7.8‒12.5(‒15.0) μm (n = 75 of 2 coll.), present only at base of stipe, absent towards the apex, very variable in shape, usually narrowly clavate to narrowly utriform, occasionally clavate, cylindrical, oblong, flexuose, hyaline, thin-walled. Clamp connections present and abundant in all examined tissues.

Habit, habitat and geographical distribution range: —Solitary, saprotrophic, on the ground under P. nigra subsp. pallasiana , which is a typical tree species of the Anatolian Region. So far, L. cremea is known only from the type locality in Denizli Province, Turkey.

Additional specimen examined: — Turkey, Denizli Province: Çamlık District , on the ground under P. nigra subsp. pallasiana , at 37°44′29.9″N, 29°5′20.2″E, alt. 438 m, 08 October 2016, O. Kaygusuz, OKA-TR11020; GenBank : ITS OL 630459 .

Figures

FIGURE 3. Basidiomata of Lepiota cremea (OKA-TR11019, holotype). Scale bars: 10 mm.

FIGURE 4. Microscopic features of Lepiota cremea (OKA-TR11019, holotype): a. Basidiospores.b. Basidia.c. Cheilocystidia.d. Elements distributed over the stipe surface. Scale bars: 10 μm.

FIGURE 5. Microscopic features of Lepiota cremea (OKA-TR11019, holotype): a. Elements of the pileus covering. Scale bar: 10 μm.