Russula bhurbanensis Razzaq, Naseer & Khalid, 2023

Razzaq, Annum, Naseer, Arooj, Shahid, Soumia & Khalid, Abdul Nasir, 2023, Morphoanatomical and molecular characterization of two new Russula species in Section Ingratae from Pakistan, Phytotaxa 592 (1), pp. 21-38 : 25-28

Russula bhurbanensis Razzaq, Naseer & Khalid sp. nov. Figures 3 & 4

MycoBank:—MB841965

Diagnosis:— Russula bhurbanensis is a medium sized species characterized by sticky, orange to dark brown, largesized pileus (7.5‒11.2 cm); adnexed and crowded lamellae; amyloid and fairly large spore (7.1‒9.9×6.1‒9.2 µm) with isolated and occasionally fused warts with rare line connections; abundant lanceolate cheilocystidia with contents.

Holotype:— Pakistan, Punjab, Rawalpindi, Bhurban , 33.9554° N, 73.4519° E, elev. 1828 m, on soil under Pinus wallichiana , solitary, 07 September 2020, Annum Razzaq BR39 ( LAH36938 , GenBank accession number for ITS: MW886216 , GenBank accession number for LSU: MW886218 ).

Etymology:—‘bhurbanensis’ is referring to the type locality Bhurban, Punjab, Pakistan.

Description: — Basidiomata medium to large sized. Pileus 7.5‒11.2 cm diameter, applanate to plano-concave when immature becoming depressed to infundibuliform at maturity, margin tuberculate-striate, cuticle sticky to viscid, peeling to half of the radius; prominent radial striations at periphery, with smooth central disc, in young specimen orange (2.3Y 4.9/12.6) margins and dark brown (7.9YR 5.6/5.6) central disc, in mature specimen centrally orange (2.3Y 4.9/12.6) becoming reddish yellow (6.7YR 6.2/11.3) with yellow (2.6Y 8.6/4) towards margins, in old specimen dark brown (0.4YR 3.5/5.3) centrally with lighter shade of brown (7.9YR 5.6/5.6) towards margins. Lamellae well developed, creamy yellow (3.9Y 9.7/0.5) with brown spots (6YR 7.2/3.6), crowded, adnexed, rarely alternating with short lamellulae in single tier, subventricose to ventricose, edge even, entire and concolorous. Stipe 6.9–12× 1.8–2.2 cm, equal to subclavate, central, longitudinally striated, yellowish-brown (9.7YR/3.3) to dark brown (5YR 3.6/5.9) patches towards the lower half of the stipe, beige (6.6B 9.9/0.6) at base. Context thin in pileus, white, hollow in stipe. Taste not recorded. Odor strongly unpleasant. Spore print not recorded.

Basidiospores [80/3/3] (7.1‒) 7.5‒8.7‒9.7 (‒9.9) × (6.1‒) 6.4‒7.6‒9.0 (‒9.2) µm, Q = 1.07‒1.13‒1.18, subglobose to broadly ellipsoid, ornamented, distant to moderately distant [(3–)4–5(–6) in a 3 µm diam. circle], mostly isolated, occasionally fused in pairs or triplets, rarely connected by fine line connections prominent hilar appendix, 0.85–2.12 µm, guttulated, amyloid. Basidia 43.4‒61.6×11.4‒15.8 µm, 4-spored, sterigmata avl =2.2‒5.5 µm, broadly clavate, content present. Basidiola 26.3 – 40.3×7.9 – 11.9 µm, cylindrical to clavate. Pleurocystidia 74.9 ‒ 119×7.7 ‒ 14.2 µm, mainly clavate, fusiform or lanceolate similar to cystidia on lamellae edge but relatively larger. Lamellar edges fertile. Cheilocystidia 72.4 ‒ 89.4×6.7 ‒ 12.2 µm, abundant, lanceolate or fusiform, apically acute to obtuse, mucronate 2‒8 µm long appendage, thin to moderately thick walled, contents crystalline like masses. Marginal cells 10.3‒20.5×4.8‒6.3 µm, small, subcylindrical to clavate. Hymenophoral trama mainly composed of numerous sphaerocytes measuring 19.3 – 29.7×15.6 – 23.4 µm. Pileipellis a mixture of cylindrical hyphae 2.26 – 8.14 μm and sphaerocytes 23.8 – 46.1×18.9 – 24.7 µm,, septate, branched, parallel in arrangement, thin walled, highly flexuous. Hyphal terminations near the pileus margin intricate, less flexuous, thin walled, terminal cells 22.7‒54.5×3.4 ‒ 9.4 µm, clavate with content. Hyphal terminations near the pileus center more flexuous, thin walled, terminal cells 18.7 ‒ 59.9×3.1‒8.1 µm, clavate, thin walled, heteromorphous content. Pileocystidia near pileus margins infrequent, 54.7‒94.4×3.2‒5.7 µm, 1‒3 celled, cylindrical, mostly clavate, apically obtuse to slightly constricted, dense content. Pileocystidia near pileus center 60.2‒91.4×2.5‒5.1 µm, more frequent, thin walled, heteromorphous content, apically obtuse to constricted, always 1- celled. Clamp connections absent in all tissues.

Additional material examined: — Pakistan, Punjab, Rawalpindi, Bhurban , 33.9554° N, 73.4519° E, elev. 1828 m, on soil under coniferous tress, 04 September, 2020, Annum Razzaq BR97 ( LAH36939 !, GenBank accession number for ITS: MW886217 , GenBank accession number for LSU: MZ343175 ) . 07 September, 2020, Annum Razzaq GB24 ( LAH36937 ! GenBank accession number for ITS: MZ686262 ) .

Figures

FIGURE 3. Macromorphological characteristics of Russula bhurbanensis A–B = BR39 (Holotype LAH36938), C–D = GB24 (LAH36937).

FIGURE 4. Microscopic characteristics of Russula bhurbanensis BR39 (Holotype LAH36938): A. Basidia; B. Basidioles; C. Pleurocystidia; D. Cheilocystidia; E. Pileocystidia (on left side) and hyphal terminations (on right side) at pileus center; F. Pileocystidia (on left side) and hyphal terminations (on right side) at pileus margin.