Metuloidea imbricata R. Saha, A.K. Dutta & K. Acharya, sp. nov.,

MycoBank number: MB 559643; Index Fungorum number: IF 559643; Facesoffungi number: FoF 11346; (Fungal Diversity Notes, 2022)


Grown on dead wood. Sexual state: Basidiocarp annual, sessile, imbricate, multipileate. Pileus 30–50 × 23–40 mm diam., 5–13 mm thick at base, coriaceous, glabrous, concentrically zonate, even, reddish grey (8B2) when fresh, becoming greyish orange (5B3) on drying. Margin distinct, even to slightly wavy, 0.7–2 mm thick, white (1A1) when fresh, greyish orange (5B3) on drying; context fibrillose, greyish orange (5B3) on drying, 0.5–2 mm thick at base. Hymenophore hydnoid; spine 1–5 mm long, conical, dense, reddish grey (8B2) when fresh, brownish orange (7C3) to brown (7E4) on drying, 4–5 per mm. Odour sweet. Taste unknown.

Hyphal system dimitic. Context dimitic; generative hyphae coralloid, solid, sometimes skelerified, 2.9–5.3 µm broad, clamped, thin- to thick-walled; skeletal hyphae 3.9‒6.7 µm broad, hyaline, unbranched, thick-walled. Spine dimitic, parallel; skeletal hyphae 3.3–6.7 µm broad, thick-walled with narrow lumen, unbranched, hyaline, (-) ve in cotton blue; generative hyphae 1.3–3.3 µm broad, thin-walled, hyaline, branched. Skeletocystidia 3.9–6.7 µm broad, subventricose, hyaline, epically encrusted, deeply rooted, thick-walled. Septocystidia 3.5–6 µm broad, apex clavate to subclavate, thick walled with adventitious septa, hyaline, smooth. Basidia 9.9–16.7 × 2.9–3.8 µm diam., clavate, hyaline, thin-walled, 4-sterigmatic with basal clamps, -ve in cotton blue. Basidiospores 2.9–3.37–4.0 × 1.3–1.88–3.4 μm, Q = 1.1–2.5, Qm = 1.90, ellipsoid to elongate, hyaline, inamyloid, non-dextrinoid, (-) ve in cotton blue, thin-walled. Asexual state: not observed.

Material examined: INDIA, West Bengal, on dead wooden logs of unknown angiosperm, 13 October 2017, R. Saha & K. Acharya (CUH AM338, holotype).

Distribution: INDIA, West Bengal, Jalpaiguri District, Apalchand forest

Sequence data: ITS: ON227062 (ITS); LSU: ON227059 (LROR)

Fig. 1 Metuloidea imbricata (CUH AM338, holotype). Field pictures of the basidiocarp. a-d. Scale bars: a-d = 10 mm.

Fig. 4 Metuloidea imbricata (CUH AM338, holotype). a Basidia. b skeletocystidia. c septocystidia. d generative hyphae of context. e skeletal hyphae of context. f generative hyphae of spine. g skeletal hyphae of spine. h basidiospores. Scale bars: a–h = 5 μm.