Pseudosperma umbonatum Jabeen, Razzaq, Aqdas, Naseer & Khalid, 2025

Jabeen, Sana, Razzaq, Annum, Aqdas, Fauzia, Iqbal, Hira, Ijaz, Hira, Izhar, Aiman, Kamran, Muhammad, Naseer, Arooj & Khalid, Abdul Nasir, 2025, Pseudosperma umbonatum sp. nov. from Himalayan forests of Pakistan, Phytotaxa 701 (1), pp. 22-40 : 30-34

Pseudosperma umbonatum Jabeen, Razzaq, Aqdas, Naseer & Khalid , sp. nov. ( Figures 4–6 )

MycoBank: MB852970

Etymology:—The specific epithet umbonatum refers to the umbonate pileus of this species.

Diagnosis:—Differs from P.obsoletum and P.perlatum by having a fibrillose pileus, ovoid to ellipsoid basidiospores (7.2–7.9 × 4.7–5.4 µm), and clavate, fusiform to ventricose occasionally septate cheilocystidia.

Holotype:— PAKISTAN, Punjab, Rawalpindi division, Murree District, Murree hills, 2290 m a.s.l., solitary or scattered, in mixed pine forests ( Pinus roxburghii , P. wallichiana , with deciduous trees like Q. incana and Q. dilatata ) on nutrient-rich soil, 12 August 2018, Fauzia Aqdus, FA361 (holotype LAH36881; GenBank ITS: PP526036; LSU: PP526037.

Description:—Pileus 1.7–3.5 cm broad, conical to obtusely conic when young, umbonate; umbo obtuse at first to slightly broad later, umbo off-white (2.5Y7/2) to brown (2.5YR2/2) and black (N1); velum remnants brown (2.5YR2/2) (found in UEH-F0025 and LAH38508), margins incurved, slightly rimose; surface dry, radially appressed fibrillose; fibrils brown (2.5Y2/2) to dark brown (2.5Y2/1) on light brown to yellow context (5Y 8/4); context off-white (7.5Y9/3) to yellowish brown (5Y8/4). Lamellae free to adnexed, close, with several tiers of lamellulae; margin entire to wavy; off-white when young becoming reddish brown (2.5YR2/2) to dark brown (2.5Y3/3) at maturity. Stipe 2.5–7.8 × 0.6–1 cm, equal to narrow from center and slightly broad towards apex and base; surface dry, smooth to fibrillose, sometimes densely strigose at apex; off-white (2.5Y7/2) when young to grayish brown (2.5Y3/1) to dull brown (2.5Y4/2) at base, becoming brownish (2.5Y2/2) with prominent dark brown fibrils (2.5Y3/1) on light brown to yellowish context (5Y9/3); basal mycelium brown; cortina not observed and presumably absent, velum remnants brown (2.5YR2/2) (found in LAH38508). Smell and taste not observed.

Basidiospores [160/8/8] (6.5)7.2–7.9(8.2) × (4.2)4.7–5.4(5.8) µm, avl× avw = 7.5 × 5 µm, Q = 1.3–1.5, avQ = 1.4, ovoid to ellipsoid, smooth, guttulate, apiculus minute, germ pore absent, yellowish brown in KOH. Basidia (20)21.4–31.9(35.8) × (5)5.5–9.5(9.8) µm, avl × avw = 26.6 × 7.5 µm, broadly clavate, 2 to 4-sterigmata; sterigmata 2‒2.6 µm in length, avl = 2.3 µm, densely guttulate, hyaline in KOH. Cheilocystidia (29.8)34.9–39.6(41) × (9.5)10.9– 11.9(12.3) µm, avl × avw = 37.2 × 11.4 µm, septate, clavate, fusiform to ventricose, hyaline. Pleurocystidia absent. Pileipellis hyphae (3.5)3.6–4.5(4.7) µm wide, avw = 4 µm filamentous, rarely branched, septate, hyaline. Stipitipellis hyphae (3.5)3.7–4.6(4.8) µm wide, avw = 4.1 µm filamentous, branched, cylindrical to clavate terminals, septate. Caulocystidia absent. Clamp connections observed in all tissues.

Additional materials examined:— Pakistan, Khyber Pakhtunkhwa,Abbottabad District,Khanspur,Himalayan moist temperate forests, 2250 m a.s.l., under P. wallichiana and Q. incana Roxb. , solitary on grass, 11 August 2018, Abdul Nasir Khalid FBSR-630 (LAH36952!; GenBank ITS PP526034); on soil, 1 September 2024, Sana Jabeen HP51D15 (LAH38507!; GenBank ITS PQ804790); on soil, 1 September 2024, Hira Ijaz HP68D23 (LAH38508!; GenBank ITS PQ804789) Punjab, Rawalpindi division, Murree District, Murree Hills, 2290 m a.s.l. solitary or scattered, in mixed pine forests ( P. roxburghii , P. wallichiana , with deciduous trees like Q. incana and Q. dilatata ) on nutrient-rich soil, 14 August 2018, Fauzia Aqdus, FA240 (LAH36883!; GenBank ITS PP526035); Rawalpindi District, Patriata, 2291 m a.s.l., on soil, 16 Aug 2020, Muhammad Kamran K16SJ65 (UEH-F0023!; GenBank ITS PP526033); Bhurban town, Chinar Golf Club, 1828 m a.s.l., on soil under mixed vegetation of Pinus spp. and Platanus orientalis L., 10 September 2020, Annum Razzaq & Abdul Nasir Khalid GC60 (UEH-F0024!; GenBank ITS PP504493); Governor House, 1828 m a.s.l., on soil under P. wallichiana 7 September 2020, Annum Razzaq & Abdul Nasir Khalid GB20 (UEH-F0025!; GenBank ITS PP504494).

Habitat & distribution:—Himalayan moist temperate forests of Khyber Pakhtunkhwa and Punjab Province of Pakistan among vegetation dominated by Pinus roxburghii , P. wallichiana , C. deodara and Quercus spp.

Figures

FIGURE 4. Pseudosperma umbonatum. A & B. UEH-F0024; C–E. LAH38508; F. UEH-F0023. Scale bars = 1 cm.

FIGURE 5. A. LAH36952; B & C. UEH-F0025; D & E. LAH36883; F. LAH36881 (Holotype); G & H. LAH38507.

FIGURE 6. Pseudosperma umbonatum (Holotype, LAH36881). A. Basidiospores; B. Basidia; C. Cheilocystidia, D. Pileipellis; E. Stipitipellis. Scale bars = 10 µm.