Inosperma pakistanicum Sana & Kiran, 2025

Kiran, Munazza & Ali, Wajid, 2025, Inosperma pakistanicum sp. nov. (Inocybaceae, Agaricales) from Swat, Pakistan, Phytotaxa 690 (1), pp. 77-88 : 82-84

Inosperma pakistanicum Sana & Kiran sp. nov. ( Figs. 2 & 3 )

MycoBank:—MB856210

Etymology:—The specific epithet “ pakistanicum ” refers to the country “ Pakistan ” from where the holotype was collected.

Diagnosis:— Inosperma pakistanicum differs from I. adaequatum in having orange to bright brown pileus, adnate and vivid purple to vivid reddish orange lamellae, broadly ellipsoid to elongate basidiospores, narrowly utriform, a few with median constriction cheilocystidia, a cutis pileipellis, presence of pileocystidia and absence of caulocystidia.

Holotype:— PAKISTAN. Khyber Pakhtunkhwa, Swat District, Aligrama Village , 34.80068° N, 72.31424° E, 908 m a.s.l. on soil under Quercus spp. , 30 July 2023, Wajid Ali AS-19 ( LAH38334 !; ITS: PQ452108 ; LSU: PQ614170 ).

Habit and Habitat:—On soil under Quercus spp. in Aligrama Village, Swat, Pakistan.

Description:—Basidiomata medium to large-sized. Pileus 30–58 mm broad, campanulate when young becoming subumbonate at maturity, margins striated when young, turning rimose or cracked at maturity, orange to yellow-orange (7.5 YR 7/6–7.5 YR 7/8) when young, and orange to bright brown (7.5 YR 7/6–7.5 YR 5/8) at maturity. Lamellae 2–5 mm broad with even or entire edges, furcated towards the margins, subventricose, 1–2 mm apart, subdistant to close, vivid purple (10P 8/12) when young turning vivid reddish orange (2.5YR 6/14) at maturity. Stipe 33–84 × 10–20 mm, central, abruptly bulbous at base, slightly fibrous surface, white when young turning vivid purple (10P 8/12) to light orange (5YR 9/6) to dark reddish brown (5YR 4/8) at maturity.

Basidiospores [40/2/2], (7.32–)–8.28–11.48–(–12.26) × (4.19–)–4.61–8.67–(–9.01) μm, [avL × avW 9.79 × 6.60 μm, Q= 1.25–1.88, Q av =1.51], broadly ellipsoid to elongate, smooth surface, usually with a round to amorphous greenish-yellow oily content, apiculus distinct. Basidia (22.20–)–22.49–27.91–(–28.31) × (7.20–)–7.28–8.35–(–8.90) μm, clavate, often with faint yellow to greenish oily droplets, 2–4 sterigmate, 2.74–3.75 μm in length,. Cheilocystidia (24.96–)–27.10–30.45–(–31.71) × (6.29–)–6.84–7.90–(–8.35) μm, narrowly utriform, few with median constriction cheilocystidia. Pleurocystidia absent. Hymenophoral trama subregular. Pileipellis, intricate trichoderm, hyphae 3.05– 5.69 μm diam, pileocystidia (32.63–)–34.91–36.23–(–37.11) × (8.79–)–9.35–12.11–(–14.67) μm, oblong. Stipitipellis a cutis, hyphae 2.41–4.10 μm, diam. Caulocystidia absent. Oleiferous hyphae 3–6 µm wide. Clamp connections present.

Additional material examined: PAKISTAN. Khyber Pakhtunkhwa, Swat District, Aligrama Village , 34.80068° N, 72.31424° E, 908 m a.s.l. on soil under Quercus spp. , 01 August 2023, Wajid Ali AS-7 ( LAH38335 !; ITS: PQ452107 ) .

Figures

FIGURE 2. A–D. Basidiomata of Inosperma pakistanicum A= Lamellae and Stipe (Paratype, LAH38335), B= Pileus (Paratype), C= Lamellae and Stipe (Holotype, LAH38334), D= Pileus (Holotype). Scale bars A= 15 mm, B= 12 mm, C= 20 mm, D= 25 mm,.

FIGURE 3. A–K. Microscopic structures of Inosperma pakistanicum (Holotype, LAH38334) A. Basidiospores, B. Basidia, C. Basidia with probasidium, D. Cheilocystidia, E–F. Pileocystidia, G. Hymenophore and hymenophoral trama, H. Oleiferous hyphae in pileus, I. Oleiferous hyphae in stipe, J. Pileipellis, K. Stipitipellis. A–C, E, H–K = 100X, D, F–G = 40X. Scale bars: A–C, K= 15 μm, D= 25 μm, E= 14 μm, F, H–J= 22 μm, G= 20 μm.