Tylopilus pseudoballoui K. Das, D. Chakr & Vizzini

Chakraborty, Dyutiparna, Vizzini, Alfredo & Das, Kanad, 2018, Two new species and one new record of the genus Tylopilus (Boletaceae) from Indian Himalaya with morphological details and phylogenetic estimations, MycoKeys 33, pp. 103-124 : 109-111

Tylopilus pseudoballoui K. Das, D. Chakr & Vizzini sp. nov. Figs 5, 6

Type.

INDIA. Sikkim, South District, Maenam WLS (Maenum 3), 2136 m alt., N27°15'34.7" E88°21'25.7", 23 Aug 2017, Quercus spp., D. Chakraborty & K. Das, DC 17-30 (CAL 1651)

Diagnosis.

Distinct from all allied taxa by sequence data (nrITS and nrLSU) and morphologically by its sticky orange-yellow pileus surface, pale yellow pore surface which turns to pale orange or greyish-orange when bruised and absence of reticulation on stipe surface.

Etymology.

referring to its being a look-alike of T. balloui , a North American species.

Description.

Pileus 60-150 mm diam., initially convex then plano-convex, surface sticky, orange-yellow to brownish-yellow (5 B–C 8), paler at margin; margin entire, plain, without any sterile flap of tissue. Pore surface pale yellow (3A3), turning pale orange to greyish-orange (6 A–B 3) on bruising; pores angular, 5-8/mm. Tubes subdecurrent, 6-10 mm long, yellowish-white, brownish on bruising. Stipe 55-110 × 20-40 mm, mostly subclavate, solid, concolorous with pileus; surface pruinose, never reticulate; basal mycelium white. Context 20 mm thick in pileus, chalky white (1A1), unchanging on exposure but turning turquoise grey (24D2-D1) with FeSO4 (chalk), pale yellow (4A3) with 5% KOH, yellowish-grey (4B3) in Guaiacol. Pileus surface brownish-red (8C8-7) on bruising, turning dark green to greenish-grey (25 E–F3– 2) in FeSO4, vivid yellow (3A8) in KOH, unchanging in NH4OH. Stipe 55-110 × 20-40 mm, mostly subclavate, solid, concolorous with pileus; surface pruinose, never reticulate; basal mycelium white. Odour pleasant. Taste slightly pungent. Spore print not obtained.

Basidiospores 6.4 –7.4– 9.9 × 3.8 –4.5– 5.7 µm (n = 30, Q = 1.5 –1.73– 2.04), ellipsoidal, thin-walled, smooth under light microscope. Basidia 22- 30 × 8-10 µm, four-spored, clavate. Pleurocystidia 40-54 × 7-10 µm, emergent up to 30 µm, fusoid to ventricose, appendiculate, yellow pigmented or hyaline, mostly with dense globular to oily content. Tube edge fertile; cheilocystidia 33-55 × 7-10 µm, common, clavate to cylindrical, subfusoid to ventricose. Hymenophoral trama divergent, hyphae septate, gelatinous, up to 5 µm wide. Pileipellis an ixocutis up to 150-280 µm thick, composed of subparallel to suberect, somewhat interwoven hyphae; terminal elements 20-70 × 6-11 µm, cylindrical to subcylindrical, sometimes subfusoid, content orange-brown pigmented. Stipitipellis up to 150 µm thick, fertile, composed of basidia and cystidia in several clusters; caulobasidia similar to that of hymenial basidia; caulocystidia 40-76 × 10-12 µm, broadly clavate to subclavate or appendiculate.

Specimens examined.

India. Sikkim: South District, Maenam WLS (Maenam 3), 2136 m alt., N27°15'34.7", E88°21'25.7", 23 Aug 2017, Quercus sp., D. Chakraborty & K. Das, DC 17-35 (CAL); Uttarakhand: Champawat district, Abbot mount, 1885 m alt., N29°25.466', E80°06.085', 18 July 2017, A. Ghosh, KD B-02 (CAL). Uttarakhand: Pauri district, 1971 m alt., N30°02.874', E79°08.221', 4 Aug 2017, K. Das, KD 17-24 (CAL).