Cortinarius pseudotorvus A. Naseer, J. Khan & A. N. Khalid, 2020

Naseer, Arooj, Garrido-Benavent, Isaac, Khan, Junaid, Ballara, Josep, Mahiques, Rafael, Khalid, Abdul Nasir & Sher, Hassan, 2020, Cortinarius pakistanicus and C. pseudotorvus: two new species in oak forests in the Pakistan Himalayas, MycoKeys 74, pp. 91-108 : 96-98

Cortinarius pseudotorvus A. Naseer, J. Khan & A. N. Khalid sp. nov. Figure 4

Diagnosis.

Cortinarius pseudotorvus is an oak-associated species that differs from C. torvus by the smaller and slender basidiomata, and by the slightly more felty surface of pilei; it has broadly ellipsoid to sub-amygdaliform basidiospores (10.9 × 7.1 µm in average).

Type.

Pakistan, Khyber Pakhtunkhwa province, Swat, Toa, Alpuri forests, 34°51'51.2"N, 72°39'48.0"E, 2800 m a.s.l., on soil under Quercus oblongata , Arooj Naseer & Abdul Nasir Khalid, 15 July 2015, AST20 (holotype: LAH35257).

Etymology.

The epithet " pseudotorvus " indicates its morphological resemblance and close phylogenetic position to Cortinarius torvus .

Description.

Basidiomata small sized and slender. Pileus campanulate when young, becoming subumbonate and sometimes flat to plano-convex in mature stages, 15-30 mm in diameter, with margins deflexed, undulate, sometimes moderately to strongly striate; cuticle light brown (8.3YR 6.7/2.5), smooth to finely or even coarsely fibrillose (felty), with dark brown (4.7YR 2.6/5.5) fibrils radiating from the center. Lamellae adnate, broad, distant and relatively thick, with an evenly smooth margin, dark brown with age (4.1 YR 1.8/3.1); lamellulae present, regular. Stipe cylindrical, up to 56 mm long, 4-9 mm at apex and 1.1-1.3 cm thick at base, which is slightly bulbous, solid; surface brown (7.8YR 4.4/4.7) becoming whitish (3Y 7.2/1.5) in upper half and the base, finely fibrillose, the 3⁄4 of stipe covered with universal veil remnants when young, and partial veil present, whitish in young specimens and brownish when mature, forming in general a persistent annulus. Context of pileus and stipe of the same color as the cuticle. Smell indistinct and taste not recorded.

Basidiospores broadly ellipsoid to sub-amygdaliform, [90/6/3] (9.2-) 9.9-11.6 (-12.5) × (6.1-) 6.7-7.7 (-8.1) µm, avl × avw= 10.9 × 7.1 µm, light yellowish brown to dark brown in 5% KOH, reddish brown in Melzer’s reagent, densely ornamented. Basidia clavate, 25-35 × 7-8 µm, 4-spored, clamped at the base, hyaline in 5% KOH, darker when stained in Congo red. Scant cellular elements in lamellar pleura cylindrical to narrowly utriform, 30-35 × 5-8 µm, and clamped at the base. Pileipellis duplex; epicutis composed of individual hyphae 3-4 µm in diameter, clamped at septa and with clavate to cylindrical terminal elements.

Ecology.

Gregarious; growing in either pure oak forests ( Quercus oblongata ) or mixed forests with oaks and pines ( Pinus wallichiana ) at an altitude greater than 2000 m a.s.l. The soil pH was around 8.4.

Additional material examined.

Pakistan, Khyber Pakhtunkhwa, District Swat, Malam Jabba valley, 34°50'57.6"N 72°33'15.7"E, on ground in mixed forests of oak and pines, Junaid Khan, 10 August 2018, MJ-15103 (LAH36368); Toa, Alpuri forests, 34°51'51.2"N 72°39'48.0"E, 2800 m a.s.l., on soil under Quercus oblongata , Arooj Naseer & Abdul Nasir Khalid, 15 July 2015, AST17 (LAH35256).

Figures

Figure 4. The new species Cortinarius pseudotorvus, AST 20 (LAH 35257, holotype). A-C Basidiomata A, B AST 20 (holotype) C MJ- 15103 (LAH 36368) D-F Basidiospores of AST 20 (holotype) observed with the SEM technique. Photo: A. Naseer (A, B), J. Khan (C). Scale bars: 10 µm (D), 5 µm (E), 2 µm (F).