Tylopilus himalayanus D. Chakr., K. Das & 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 : 107-109

Tylopilus himalayanus D. Chakr., K. Das & Vizzini sp. nov. Figs 3, 4

Holotype.

India. Sikkim: East District, Upper Chandmari, 1977 m alt., N27°23'13.7", E88°46'42.9", 26 Aug 2017, D. Chakraborty & K. Das, DC 17-25 (CAL 1649).

Diagnosis.

Distinct from all allied taxa by a combination of sequence data (nrITS and nrLSU), reddish- or brownish-grey to purplish-grey, then brown to reddish-brown pileus in basidiomata, absence of olive or violet tinges on stipe surface, presence of angular pores, stipe without reticulum or rarely with a faint reticulum restricted to the very apex, bitter taste of the context, positive reaction of the stipe context with KOH (dark orange) and FeSO4 (dark green) and medium sized (10.9-14.4 × 3.9-4.9 µm) basidiospores.

Etymology.

Referring to Indian Himalaya, the type locality.

Description.

Pileus 71-120 mm diam., initially convex then plano-convex to applanate, surface dry, matte to somewhat subvelvety, faintly areolate, brownish-grey, dull red, reddish-grey to purplish-grey or greyish-magenta (11 –13B–C2– 3) when young, gradually brown to reddish-brown (7E4-9D4) or darker, paler greyish-yellow (4C4) towards margin, pale yellow (2A3) at margin; margin entire, decurved to plane with a narrow flap of tissue, blond (4C4). Pore surface greyish-yellow (3C4) when young, pinkish-white (8A2) with age, turning greyish-brown (6D3) on bruising; pores angular, 2/mm. Tubes adnexed to subdecurrent, 5-6 mm long, whitish-brown to brownish, light brown to brown (26B2-3) on bruising. Stipe 95-155 × 20-32 mm, mostly subclavate, hollow, pale yellow (1-2A3) at apex, brownish towards base but never violaceous; surface usually without any reticulum, but sometimes faintly reticulate at apex (1/8th from the juncture), the rest longitudinally striate. Context up to 16 mm thick in pileus, milk white (1A2), unchanging when exposed. Stipe context turning dark green with FeSO4, dark orange with 5% KOH, orange with 10% NH4OH. Taste bitter. Spore print not obtained.

Basidiospores 10.9 –12.5– 14.4 × 3.9 –4.5– 4.9 µm, (n = 30; Q = 2.51 –2.75– 3.25), elongated to fusiform, inequilateral, thin-walled, smooth under light microscope. Basidia 30-40 × 9-10 µm, four-spored, clavate. Pleurocystidia 27-54 × 8-10.5 µm, emergent up to 30 µm, fusoid to ventricose, appendiculate. Tube edge sterile; cheilocystidia 32-48 × 5.2-8 µm, common, clavate to cylindrical, subfusoid to ventricose. Hymenophoral tra ma divergent, hyphae septate, gelatinous, up to 6 µm wide. Pileipellis a trichoderm, up to 150 µm thick, composed of erect hyphae, somewhat interwoven, encrusted, brown pigmented; terminal elements 20-50 × 5-10 µm, cylindrical to subcylindrical, sometimes subfusoid, content brown pigmented. Stipitipellis a cutis, made up of sub-parallel repent hyphae; caulocystidia not observed; caulobasidia similar to that of hymenial basidia.

Specimens examined.

India. Sikkim: Upper Chandmari, 1977 m alt., N27°23'13.7", E88°46'42.9", under Pinus sp. in temperate mixed forest, 26 Aug 2017, D. Chakraborty & K. Das, DC 17-31 (CAL); Uttarakhand: Champawat district, Abbot mount, 1933 m alt., N29°25.465', E80°06.422', under Cedrus deodara in temperate coniferous forest, 18 Jul 2017, A. Ghosh, KD B-03 (CAL).