Suillus adhikarii K. Das, D. Chakr. & Cotter, 2015

Das, Kanad, Chakraborty, Dyutiparna & Cotter, Henry Van Tuyl, 2015, Suillus adhikarii, a new species from the subalpine Himalaya of India and Nepal associated with Larix, Phytotaxa 219 (3), pp. 289-295 : 290-293

Suillus adhikarii K. Das, D. Chakr. & Cotter , sp. nov. ( Fig. 1 , 2 , and 3)

Mycobank:—MB 812337

Diagnosis:— Suillus adhikarii is distinct by conic to acute umbo on pileus, intense yellow to yellow pore surface that becomes orange-brown to brown after bruising and/or with age, a distinct collar-like cinnamon brown zone with concolorous reticulum on stipe apex above annulus and occurrence with Larix .

Type:— INDIA. Sikkim: Dombang, 2890 m, N27°44’07.0” E88°44’38.0”, under Larix griffithiana , subalpine mixed (coniferous and broad leaf) forest, 18 August 2011, K. Das, KD 11-007 (Holotype CAL!).

Etymology:—Commemorating Dr. M. K. Adhikari for his contributions to the mushrooms of Nepal.

Pileus 25–85 mm diam., convex when young, becoming plano-convex with a conic to acute umbo at all developmental stages, surface viscid to glutinous, with anastomosing fine radially arranged veins and squamules, dark brown (6–7 F 8) to reddish brown (9D4–6) with paler margin when very young then brown (6D8) with darker (6 E 8)

disk and pale yellow (3–4 A 3 margin) or brown orange (6 C 5) with brown (6D6) disk and pale orange (5 A 3) margin,

when mature fairly uniform light to gray orange (5 A – B 4) or brown (7 E 8) grading to light orange margin (6 A 4);

margin entire, decurved with a narrow flap of sterile tissue. Pore surface greyish yellow (1 B 3) to light yellow (3 A 4)

when young, pastel yellow to yellow (3 A 4–4 A 6) turning greyish orange (6 B 3–4), brownish orange (6 C 4) or darker after bruising or with age; pores compound, angular or somewhat irregular, 1–2 per mm. Tubes decurrent, of different length, 3–6 mm long, concolorous with pore surface. Partial veil present; pale yellow (3 A 3) cottony mycelium inside with clear, becoming brown (6 E 8) glutinous on the outside; leaving remnants on cap margin and superior annulus 5–9

mm wide, annulus appressed to stipe and glutinous on outside, may be indistinct in mature basidiomata. Stipe 30–70

× 5–13 mm, cylindric with subbulbous base, surface reticulate above annulus becoming faintly reticulated below towards the half of the stipe length, apex pastel yellow to yellow (3 A 4–4 A 6), then gradually mixing with light orange,

orange to dark orange (6 A 5–6, 5 A 6–8) and/or brownish orange (6 C 8) to cinnamon brown making a collar-like zone with concolorous reticulum, below annulus greyish orange to greyish red (6 B 4–7 B 4) and brownish orange (7 C 4) on pale yellow to light yellow background, with white basal cottony mycelium at base, slightly darker after bruising or with age. Pileus context light yellow (1–2 A 3–5) with white beneath pileus cuticle, dulling and browning a little on exposure, pale green tones developing if water soaked, turning olive gray with FeSO 4; greenish then blue green with KOH; pale orange with narrow brown halo NH 4 OH then blue green and clay pink with guaicol. Stipe solid, light yellow (2 A 4) becoming light yellow to yellow (1 A 6 to 2 A – B 4–5) then gray yellow (3 B 4–5 usually with 3 C 5 at base),

sometimes slowly paler after long exposure. Pileus surface slowly turning pale grey with FeSO4; olive black with

KOH; slowly yellow olive with narrow pale gray halo with NH 4 OH. Taste and smell indistinct. Spore print light brown to brown (5D5 to 6 E 8). Pileus stains paper yellow when making spore prints.

Basidiospores 9.0–11.0–12.3 × 4.0–4.8–5.7 μm (n = 40, Q = 1.75–2.28–2.67), subfusiform to elliptic, inequilateral,

smooth, thin-walled, hilum conspicuous, brown orange in Melzer’s. Basidia 20–25 × 7–8 μm, hyaline to pale yellow in H 2 O and KOH, thin-walled, 4-spored, clavate; sterigmata up to 4 μm long. Pleuro- and cheilocystidia 60–79 × 8–10 μm, emergent to 35 μm, common, subfusiform to cylindrical with appendiculate, capitate to rounded apex, with incrustations, content slightly dense. Hymenophoral trama divergent, gelatinous, tramal hyphae up to 5 μm wide,

septate with abundant laticifers; oleiferous hyphae up to 9.5 μm wide, dark brown. Pileipellis up to 180 μm thick,

ixocutis to ixotrichoderm, composed of repent to suberect twisted to wrinkled, septate, up to 5.7 μm wide hyphae, hyaline to ochraceous in KOH. Pileus trama of somewhat tightly interwoven, periclinally arranged, simple septate, hyaline hyphae 4.5–10.5 μm wide. Stipitipellis fertile, composed of basidia, basidiole and cystidia; caulocystidia 40–57 × 6–9.5 μm, slightly thick-walled (0.5 μm), subclavate to cylindrical with rounded to subcapitate apex, with incrustations; caulobasidia 19–30 × 6–8 μm, 2–4-spored, subclavate to clavate. Clamp connections absent in all parts.

Cultural characteristics (Cultures VC 1230, VC 1449) on modified Hagem’s agar ( Fig. 3 ): Macroscopic features variable. Colony felty overlaid with open cottony, bumpy, wrinkled, radial furrows; margin open cottony with villose edge or low cottony fuzzy; outline somewhat irregular; raised and submerged hyphae equal at margin; all white to yellow white (3 A – B 1.5) ± light brown (5D4) rings or center gray orange (4 B 3), middle mottled light yellow (3–4 A – B 2–4) and white, margin white. Reverse indistinct radial furrows; center and middle dark orange brown to red brown, margin yellow white to yellow orange. After 4 weeks of incubation, colonies were 17–33 mm in diam with mycelium growing 1–4 mm above the agar surface and 2–4 mm deep into the agar. Syringaldazine positive or negative; gum guaiac positive or negative; KOH brown to red brown; NH 4 OH no reaction or red purple on margin only, halo absent or weak purple and orange or red purple.

Microscopic features variable. Slide culture: leading hyphae 2–3.5(–4) μm wide; clampless. Petri dish culture:

oleiferous hyphae gray golden to golden brown; vesicular cells and hyphal strands sometimes present.

Habitat/distribution:—Growing in groups or gregariously under Larix griffithiana (Lindl. & Gordon) Carrière and L. himalaica W.C. Cheng & L.K. Fu in subalpine coniferous or mixed forests in India and Nepal.

Additional specimens examined: INDIA. Sikkim: North District, Shingba Rhododendron Sanctuary , 3095 m, N27°43’48.6” E88°44’32.0”, under L. griffithiana , subalpine coniferous forest, 25August 2011, KD 11-097; NEPAL. Rasuwa District: Langtang National Park, 3070 m, under Larix himalaica , 6 August 1985, H. V. T. Cotter, VC 1230 ( KATH, NY); ibid., Langtang National Park, 3140 m, under L. himalaica , 11 October 1985, VC 1449 ( NY).

Figures

FIGURE 1. Suillus adhikarii (KD 11-007): a & c. Fresh basidiomata in field b. Concolorous background color and reticulation of stipe above annulus d. Pore surface e. Compound pores (from dry material) f. Radial section through pileipellis g. Hymenial cystidia h. Basidiospores. Bars: e = 1000 μm, f = 50 μm, g–h = 10 μm.

FIGURE 2. Suillus adhikarii (KD 11-007) a. Basidiospores b–c. Caulocystidia d. Caulobasidia e. Tube basidia f. Radial section through pileipellis g. Pleuro- and cheilocystidia. Bars: a–g = 10 μm.

FIGURE 3. Suillus adhikarii (VC 1449) 30-day-old culture on Hagem’s agar in a 9-cm-diam Petri plate. Dark reddish guttate droplet formed on colony.