Boletus recapitulatus D. Chakr., K. Das

Chakraborty, Dyutiparna, Das, Kanad, Baghela, Abhishek, Singh, Sanjay K. & Dentinger, Bryn T. M., 2015, Boletus recapitulatus (Boletaceae), a new species from India with peculiar mushroom-shaped cells, Phytotaxa 236 (2), pp. 150-160 : 151-152

Boletus recapitulatus D. Chakr., K. Das , A. Baghela, S.K. Singh & Dentinger sp. nov.

Mycobank:—MB 811961

GenBank:—KP938967.

Diagnosis:— Boletus recapitulatus is distinguished by having a low reticulum on the stipe surface, sticky reddish cap, presence of a sterile flap at pileus margin, adnate to subdecurrent tubes, angular pores with red pore mouths, yellow context quickly turning blue on exposure, narrow spores (8.0– 10.4 –12.3 × 3.2– 4.0 –5.5 μm), brown-pigmented hymenial cystidia, distinctly capitate to mushroom-shaped tips of terminal cells in pileipellis and stipitipellis, and occurrence under Betula alnoides .

Type:— India, Sikkim, East District, Churten, 1454m, N 27°34’10.9” E 88°25’51.9”, 25 thMay, 2014, K. Das, DC 14-001 (Holotype CAL!).

Etymology: recapitulatus refers to the recapitulation of the mushroom-shape among terminal cells of hyphae in the pileipellis and stipitipellis.

Pileus 30–90 mm diam.; convex when young, becoming plane at maturity; surface matted to subvelvety, slightly glutinous in young basidiomata, reddish brown (9D6–8), unchanging after bruising, caramel brown (6 C5–6 ) with KOH ; margin regular to undulating with narrow sterile flap of tissue, light yellow to yellow (3 A5–6 ). Pore surface slightly depressed near stipe, pastel yellow to light yellow (3 A4–5 ) when young, gradually becoming pale orange, finally with red pore mouth on yellow background, turning greenish blue quickly after bruising ; pore 2–3/mm, simple, angular. Tube 5 mm long, adnate to subdecurrent, light yellow (2 A5 ), quickly becoming bluish when bruised. Stipe 20–75 × 13–28 mm, central, with distinct red to brownish red (9 B – C8 ) low (pseudo) reticulum over vivid yellow background (3 A8 ) at juncture of pore surface and stipe, then just beneath the juncture brownish red to violet red (10D7– 6, 10E 5) reticulation on pastel red (8 A4 ) background, reticulation gradually indistinct towards base. Context mostly solid, off-white to light yellow (2 A4–5 ) except the stipe base which is distinctly yellow (up to 3 A6 ), quickly becoming bluish when exposed, turning greyish orange to brownish orange (5 B4–5 C5 ) with KOH, greyish yellow (3 C3–4 ) with FeSO 4, dull red (9 C3 ) with guaiacol. Odor indistinct. Taste mild. Spore print olive brown (4 E8–4 F8 ) .

Basidiospores 8.0– 10.4 –12.3 × 3.2– 4.0 –5.5 μm (n = 30, Q = 1.96– 2.64 –3.23), elliptic to oblong, inequilateral, smooth under light microscope and under SEM with very high magnification (×120000) minutely warty, greenish. Basidia 17–35 ×47–9.5 μm, 4-spored, clavate to subclavate; sterigmata 5.5–16 ×1.8–9 μm. Pleurocystidia 26–60 × 4.6–10 μm, emergent 20–36 μm, common, subcylindrical, subfusiform to ventricose-rostrate or appendiculate, content dense, slightly granular, brown pigmented. Tube edge fertile, composed of basidia, cheilocystidia and chains of orange-brown pigmented palisade cells. Cheilocystidia 20–37 × 5–8 μm, common, slightly emergent (20μm), ventricose-rostrate to subcapitate to subappendiculate, contents orange-brown pigmented, granular. Hymenophoral trama divergent, tramal hyphae 6.6–8 μm wide, mostly twisted, gelatinous. Pileipellis 130–155 μm thick, trichoderm to ixotrichoderm, composed of erect septate hyphae, sometimes slightly interwoven; terminal cells 81–162 × 14–21 μm, cylindrical with rounded, subfusoid to subcapitate or distinctly capitate (or mushroom-shaped), content slightly dense. Stipitipellis 66–116 μm thick, fertile, ixotrichoderm, composed of hyphae, basidia and cystidia; caulocystidia 35–43 × 5–8 μm, subfusoid to clavate, or with rounded to subcapitate apex, contents brown; hyphae 3–5 μm wide, erect with rounded to subfusoid apex; caulobasidia similar to tube basidia but less in number. Clamp connections absent.

Habitat/ Distribution: Growing in groups or gregariously under Betula alnoides Buch. -Ham. ex D. Don in subtropical broadleaf forest.

Specimens examined: India, Sikkim, East District, Churten , 1454 m, N 27°34’10.9” E 88°25’51.9”, 25 thMay, 2014, K. Das, DC 14-001 (Holotype CAL!) ; ibid. East District, Churten , 1454 m, N 27°34’10.9” E 88°25’51.9”, 18 th July, 2014, D. Chakraborty, DC 14-033( CAL!) .