Pseudosperma pamukkalense Kaygusuz, Bandini & Knudsen, 2023

Kaygusuz, Oğuzhan, Bandini, Ditte, Knudsen, Henning & Türkekul, İbrahim, 2023, Pseudosperma pamukkalense (Inocybaceae: Agaricomycetes), a new species from Turkey, Phytotaxa 599 (4), pp. 225-238 : 230

Pseudosperma pamukkalense Kaygusuz, Bandini & Knudsen sp. nov. ( Figs. 2–4 )

MycoBank: —MB844004

Holotype:— TURKEY. Denizli Province: Pamukkale district, around Bağbaşı , on the soil under Pinus nigra subsp. pallasiana , at 37°43′50.5″N, 29°07′53.8″E, alt. 455 m, 05 September 2017, leg. O. Kaygusuz, OKA-TR1671 ; GenBank: ON468479 for nrITS, ON468481 for nrLSU.

Diagnosis:— Differs from Pseudosperma rimosum (Bull.) Matheny & Esteve-Rav. ( Matheny et al. 2020: 31) by a combination of pale straw to brownish yellowish tinged pileus colour and smoother pileus surface, larger basidiospores (on av. 12.9 × 7.0 μm), a whitish stipe, narrowly to broadly clavate cheilocystidia and longer caulocystidia of more than 100 μm.

Etymology:— The species was named after Pamukkale district of Denizli Province, Turkey, where the fungus was first collected.

Description:—Pileus 20–45 mm wide, at first subconical, convex to expanded, without umbo or with less pronounced low large umbo; margin at first decurved, later straight or flaring and uplifted with age and then somewhat depressed around the umbo; velipellis missing or only very faint and fugitive; surface dry, smooth to appressed finely innately fibrillose or slightly rimose, splitting deeply radially, even later smooth towards and at the umbo; pale light straw yellow to ochraceous towards center or pale reddish-brownish with yellowish tinge, paler towards margin; with age getting somewhat streaky brownish in parts. Lamellae crowded (ca. 80–100 (120), l = 1–3), adnexed to sinuate, even to subventricose, at first white to creamy white, later yellowish-brown, edges whitish to pallid and fimbriate. Stipe 30–50 × 2–7 mm, cylindrical, equal, white and remaining whitish with age or only slightly discolouring from base, slightly floccose in transverse belts, especially in the lower half. Context white to whitish, lacking any colour changes where cut or bruised. Odour (sub)spermatic. Taste indistinct.

Basidiospores (10.5‒)11.0‒15.5(‒19.0) × (5.9‒)6.3‒7.8(‒9.0) μm (n = 130 of 3 coll.), L m × W m = 12.9 × 7.0 μm, Q = (1.4‒)1.6‒2.1(‒2.5), Q m = 1.9, a minority subphaseoliform, guttulate, smooth, thick-walled, pale brown in 3% KOH. Basidia (31‒)33‒41(‒48) × 12‒13(‒14) μm, clavate to broadly clavate, strongly tapering toward base, 4- or occasionally 2-sterigmate, with granular contents, thin-walled. Pleurocystidia absent. Lamellar margin sterile. Cheilocystidia (17‒)28‒59(‒72) × (9‒)11‒19(‒29) μm (n = 80 of 2 coll.), L m × W m = 44 × 15 μm, Q = (‒1.6)2.1‒3.8(‒ 5), Q m = 3, abundant, most frequently narrowly to broadly clavate, with short- to long pedicel, a few subutriform or oblong, thin-walled, hyaline with 3% KOH. Pileipellis cutis, composed of fusiform, conical or lageniform elements, (68–)77‒169(–180) × (15–)19–29(–37.5) μm (n = 40 of 2 coll.), L m × W m = 113 × 24 μm, Q = (‒2.6)3.2‒7.2(‒7.7), Q m = 4.8, broadly mucronate, acuminate or obtuse at the apex, thin-walled, hyaline with 3% KOH. Caulocystidia only near the apex, (30–)42–91(–103) × (6–)8–15(–23) μm wide hyphae (n = 30 of 2 coll.), L m × W m = 63 × 12 μm, Q = 3.3‒7.3(‒10.2), Q m = 5.2, which are cylindrical to clavate, with obtuse to rostrate apex, thin-walled, hyaline with 3% KOH. Stipitipellis a cutis of 2.5–5(–8) μm wide cylindrical hyphae, thin-walled, hyaline with 3% KOH. Clamp connections present in all parts examined.

Habit, habitat and distribution:— Scattered singly or in groups on soil, from early to late September, mostly present at elev. 450 m, under Pinus nigra subsp. pallasiana , which is one of the most widely grown tree in western Anatolia, on sandy calcareous soils. Currently known only from the Aegean region of Turkey (Denizli Province).

Additional specimens examined:— TURKEY. Denizli Province: Pamukkale district, around Bağbaşı , on the soil under P. nigra subsp. pallasiana , at 37°43′49.5″N, 29°07′53.0″E, alt. 457 m, 24 September 2018, leg. O . Kaygusuz ( OKA-TR1672 ; nrITS: ON468480 , nrLSU: ON468482 ); ibid., under P. nigra subsp. pallasiana , at 37°43′48.5″N, 29°07′55.4″E, alt. 456 m, 28 September 2020, leg. O . Kaygusuz ( OKA-TR1673 ) .

Figures

FIGURE 2. Pseudosperma pamukkalense: Basidiomata in the natural habitat. a. Collection OKA-TR1671 (holotype). b. Collection OKA- TR1672. Scale bars: 20 mm.

FIGURE 3. Microscopic structures of Pseudosperma pamukkalense (OKA-TR1671; holotype). a. Basidiospores. b. Basidia. c. Cheilocystidia. Scale bars: 10 μm.

FIGURE 4. Microscopic features of Pseudosperma pamukkalense (OKA-TR1671; holotype). a. Pileipellis. b. Caulocystidia. Scale bars: 10 μm.