Strobilomyces pteroreticulosporus Antonín & Vizzini, 2015

Antonín, Vladimír, Vizzini, Alfredo, Ercole, Enrico & Leonardi, Marco, 2015, Strobilomyces pteroreticulosporus (Boletales), a new species of the S. strobilaceus complex from the Republic of Korea and remarks on the variability of S. confusus, Phytotaxa 219 (1), pp. 78-86 : 81-82

Strobilomyces pteroreticulosporus Antonín & Vizzini , sp. nov. ( FIGURES 3–5 )

MycoBank MB 812008

Pileus 75–110 mm, entirely covered with pyramidal, fibrillose, dirty whitish scales with black apex. Tubes pale dirty cream or greyish, darkening to black in old specimens. Pores pale dirty cream, becoming black on touching. Stipe 100–140 × 11–20 mm, cylindrical, entirely black adpressed fibrillose-scaly. Annulus distinct. Context dirty whitish greyish, immediately brownish reddening and then blackening when cut. Basidiospores (8.5–)9.5–12(–13) × (8–)9–10.5(–11.5) μm, Q = 1.06, globose to subglobose, with a completely reticulate, up to 2(–3) μm tall ornamentation. Cheilocystidia 37–70 × 15–26 μm, fusoid, sublanceolate, obtusely, rarely subacutely rostrate. Pleurocystidia similar to cheilocystidia. Clamp connections absent.

Holotype:— REPUBLIC OF KOREA, Hamyang , Hamyangsangrim, coord. 35°31’32” N, 127°43’07” E, alt. c. 200 m, 9 July 2008, V. Antonín 08.88 ( BRNM 718716 ; isotype TO HG090708 S).

Etymology:—Having basidiospores with a completely reticulate ornamentation up to 2(–3) μm tall and remembering wings.

Basidiomata single. Pileus 75–110 mm broad, convex-hemispherical, conical-convex to convex, pileipellis distinctly overlapping the pileus margin, entirely covered with pyramidal, fibrillose, dirty whitish scales with black apex, pileus surface hardly visible among the scales when young, later showing a whitish ground; velar remnants at pileus margin dirty whitish. Tubes emarginate and attached with tooth, ventricose, up to 30 mm high, pale dirty cream or greyish (6C1), darkening to black in old specimens. Pores smaller, up to 1.5 × 1 mm, towards margin and larger, up to 1.5 × 2 mm and slightly radially prolonged, towards stipe, later 1–3 mm wide, dissepiments rather thin, pale dirty cream, becoming black on touching. Stipe 100–140 × 11–20 mm, cylindrical, subclavate, up to 30 mm wide at base, ground whitish, entirely adpressed black fibrillose-scaly, scales sometimes forming an irregular net; base with pale greyish tomentum. Annulus distinct, thick (up to 3 mm), rugulose and finely tomentose in upper part, irregularly, up to pyramidally fibrillose scaly in lower part, dirty white to greyish, becoming black on touching, especially at edge; almost disappearing when old. Context dirty whitish greyish, immediately brownish reddening and then blackening when cut, with fungoid and slightly spicy smell.

Basidiospores (8.5–)9.5–12(–13) × (8–)9–10.5(–11.5) μm, average 10.8 × 10.4 μm (without ornamentation), E = 1.0–1.13, Q = 1.06, globose to subglobose, with a completely reticulate ornamentation up to 2(–3) μm tall, brown in KOH. Basidia 31–46 × 18–24 μm, 4-, less frequently 2- and 3-spored, broadly clavate or pyriform. Basidioles 17–40 × 7–21 μm, broadly clavate, sometimes subcapitate. Cheilocystidia numerous, 37–70 × 15–26 μm, fusoid, sublanceolate, thin-walled, ± obtusely, rarely subacutely rostrate, rostrum rarely subcapitate, colourless to brown in KOH (with transient shades). Pleurocystidia similar to cheilocystidia, but not so frequent. Subhymenium hyphae ± cylindrical, thin-walled, not gelatinized, often short-celled, colourless, 3–10 μm wide. Trama hyphae of cylindrical or fusoid cells, gelatinized, thin-walled, colourless, 5–17 μm wide. Pileus scales of ± cylindrical, short-celled, finely incrusted, thin- to slightly thick-walled, 5–15 μm wide hyphae; terminal cells 20–70 μm long, obtuse; basal parts colourless, apical cells dark brown in KOH. Stipitipellis a cutis of cylindrical, parallel, thin- to slightly thick-walled, 3–7 μm wide hyphae, brownish to brown in KOH. Stipe velar remnants of similar, interwoven, sometimes branched, smooth or minutely incrusted hyphae of cylindrical or subfusoid cells, thin- to slightly thick-walled, 3–15 μm wide; terminal cells cylindrical, subfusoid, (sub)clavate, 20–60 × 5–20(–40) μm, with colourless basal and brown upper part in KOH. Clamp connections absent.

Habitat:—On soil, under Quercus acutissima and Carpinus tschonoskii (BRNM 718716), or under Pinus koraiensis (BRNM 766847).

Materials studied:— REPUBLIC OF KOREA, Hamyang , Hamyangsangrim , coord. 35°31’32” N, 127°43’07” E, alt. c. 200 m, 9 July 2008, V. Antonín 08.88 (holotype BRNM 718716 ; isotype TO HG090708 S). Songnisan National Park, Bo-Eun gun, coord. 36° 31’ 54” N, 127° 49’ 28” E, alt. c. 350 m, 15 August 2013, V. Antonín (13.160), R. Ryoo and K.- H. Ka ( BRNM 766847 ) .

Remarks:— Strobilomyces pteroreticulosporus is characterized in having moderately basidiomata, a pileus entirely covered with pyramidal scales, a stipe with a thick layer of velar remnants, a well-developed annulus when young, reddening and then blackening context when cut, and moderately large basidiospores with a distinct high reticulate ornamentation.

Figures

FIGURE 3. Strobilomyces pteroreticulosporus (Basidiomata, holotype). REPUBLIC OF KOREA, Hamyang, Hamyangsangrim, 9 July 2008. Photo V. Antonín.

FIGURE 4. Strobilomyces pteroreticulosporus (Basidiomata, holotype). SEM microphotograph of basidiospores. Photo L. Ilkovics.

FIGURE 5. Strobilomyces pteroreticulosporus (holotype). a. Cheilocystidia, b. Basidia, c. Basidiospores, d. Pileipellis. Scale bar = 20 μm for a‒c, 40 μm for d.