Leucopaxillus pakistanicus R. Khan, S. Ullah & Khalid

Khan, Rameez, Ullah, Shariat & Khalid, Abdul Nasir, 2024, Leucopaxillus pakistanicus, a new species of (Tricholomataceae: Basidiomycota) from the coniferous forest of Pakistan, Phytotaxa 652 (2), pp. 149-156 : 150-151

Leucopaxillus pakistanicus R. Khan, S. Ullah & Khalid , sp. nov. ( Figs. 1–4 ) MycoBank No.: MB848423

Etymology:— The specific epithet “ pakistanicus ” (Latin) refers to Pakistan, the country in which the type locality is.

Diagnosis:— Pileus brick red or red-brown, slightly thin fleshed; lamellae creamy and thick, short decurrent gills attachment, glutulated; stipe long, cylindrical to subcylindrical, and small in diameter, broadly fistulose, spores thick-walled, cheilocystidia with subcapitate apex.

Type: PAKISTAN. Khyber Pakhtunkhwa Province, Skyland coniferous forest (35°04’35°46ʹʹ N, 71°32’72°22ʹʹE), (3140 m a.s.l.) on soil and leaf litter under Conifers forest, 5 September 2021, Rameez khan & Abdul Nasir Khalid RZ-SL-39 (Holotype, LAH37520 : GenBank OP538064).

Description:— Basidiomata medium to large sized and thick fleshed., Pileus 3–6 cm diameter, convex with an inrolled margin in young stage, becoming broadly convex to nearly flat, dark brick or red-brown (7.5RP 4/4), surface smooth and dry, finely velvety, glabrous when wet, margins white and striate, entire to slightly incurved in a young stage, wavy in the mature stage, context fleshy and white with no change in color upon bruising. Lamellae creamy, short decurrent, crowded, broad, thick, rugulose on the side surface, even and entire at edge; lamellulae present in series of 2–3, creamy. Stipe 3–5 × 0.8–1 cm, creamy, central, cylindrical to slightly tapering upward, sub bulbous at the base, firmly attachment, smooth to slightly fibrillose, broadly fistulose. Spore print white. Annulus and volva absent. Odor and taste were not recorded, ( Fig. 1 ).

Basidiospores [50/5/5] (3) 3.5–4.3 (4.7) × (2.5) 2.8–3.6 (3.8) µm, Q= (1.15) 1.2–1.4 (1.5), Qav= 1.24, broadly ellipsoid to subglobose, small, thick-walled, amyloid, hyaline, ornamented; apiculus present, hyaline in 2% KOH, Basidia narrowly clavate; thin-walled 4-spored, sterigmata 1.5–3 µm long. Cheilocystidia 23–30 × 5–7 µm, narrowly uniform to flexuose with an obtuse to sub-capitate apex, thin-walled and hyaline in KOH. Pleurocystidia absent. Hymenophoral trama 4–7 µm, parallel regularly arranged, branched, clamped at septa, hyaline in KOH. Pileipellis is a cutis of smooth filamentous, 2.5–6 µm wide; hyaline in KOH; subcylindrindrical, branched, clamped connection present at septa. Stipitipellis 3–5 µm wide, filamentous, branched, subcylindrindrical, clamped connections present, hyaline as shown in Fig 4 .

Additional specimens examined:— PAKISTAN. Khyber Pakhtunkhwa Province, Skyland coniferous forest (35°04’35°46ʹʹ N, 71°32’72°22ʹʹE), (3100 m a.s.l.) on soil and leaf litter under Conifer forest, 12 August 2022, Rameez khan & Abdul Nasir Khalid RZ-DR-249 (Paratype, LAH37521: GenBanK: OQ851496).

Figures

FIGURE 1. Basidiomata of Leucopaxillus pakistanicus sp. nov. A–B. RZ-SL-39, holotype (LAH37520); C & D additional specimens RZ-DR-249 Isotype (LAH37521). Scale bars:A= 1.5 cm, B= 1 cm, C= 1 cm. Photographs by: Rameez Khan.

FIGURE 2. Molecular phylogenetic analysis by maximum likelihood (ML) method based on combined ITS sequences. The evolutionary history was inferred by using the RAxML. Bootstrap values>70% based on 1000 replicates are shown at the branches.

FIGURE 3. Molecular phylogenetic analysis by maximum likelihood (ML) method based on combined ITS & LSU sequences. The evolutionary history was inferred by using the RAxML. Bootstrap values>70% based on 1000 replicates are shown at the branches.

FIGURE 4. Microscopic characters of Leucopaxillus pakistanicus sp. nov. A. Basidiospore. B. Basidia. C. Cheilocystidia D Pileipellis hyphae. E. Stipitipellis. Bar: A = 7 μm, B = 14 μm, C = 8 μm, D = 9 μm, E = 12 μm. Photographs by Rameez Khan.