Helvella subtinta 2020

Helvella subtinta M. Zeng, Q. Zhao & K.D. Hyde 2020

Index Fungorum number: IF556789; Facesoffungi number: FoF 06591

Holotype: CHINA, Yunnan Province, ShangriLa, on sand soil in the coniferous forests, alt. 4131 m, 16 August 2018, M. Zeng, ZM 34 (KUN-HKAS 104666, holotype; MFLU 19-1557, isotype).

Morphological description

Sexual morph Apothecia semi-hypogeous, scattered to gregarious. Pileus 0.5–2.5 cm high, 1–5 cm broad, cupulate, black, margin cracked slightly, hymenium glabrous, dark brown to black. Receptacle surface black, pubescent. Stipe 2–3 cm long, 0.5–1 cm broad, black, externally sulcate. Medullary excipulum 150–230 µm broad, of textura intricata, hyaline, composed of 3–4 µm broad hyphae. Ectal excipulum 50–120 µm broad, of textura angularis, composed of 18–23 × 11–15 internal cells, hyaline to brownish, 20–28 × 12–14 μm elongated terminal cells, brown, outermost cells catenuliform in long fascicled tufts. Stipitipellis 40–100 µm, of textura angularis, comprised of 12–17 × 9–12 μm, hyaline to brownish, internal cells, terminal cells 19–26 × 9–13 μm, brown, elongated. Asci 208–262 × 13–16 µm, 8-spored, pleurorhynchous, subcylindrical to clavate, J-, apical ring. Paraphyses 3–4 µm broad in the middle, filiform, exceeding the asci, apex enlarged, 4–6 µm broad, brown to dark brown, J-. Ascospores [20/1/1, in H ₂O] (14.6–)15.3–18.1(–19.6) × (10–)10.2–11.8(–12.5) (Q = 1.32–1.81, Q = 1.52 ± 0.14), 1-seriate, ellipsoid, smooth-walled with a large oil droplet. Asexual morph Undetermined.

Habitat: coniferous forests.

Distribution:China.

GenBank Accession: ITS：MN449991；LSU：MN449992.

Notes: This species is characterised by its semi-hypogeous, black cupulate apothecia, black hymenium, sulcate stipe, dark brown paraphyses and pleurorhynchous asci. The phylogenetic tree (Fig. 103) indicates a closed relationship with Helvella tinta Q. Zhao, B. Feng & K.D. Hyde. Helvella tinta has cupulate to irregularly cupulate pileus with white to smoky grey stipe and mottled hymenium with patches of paler pigmentation hymenium (Hyde et al. 2016). Across the LSU sequences, there are 52 notable nucleotides include 6 gaps differences among the 890 analysed nucleotides between H. tinta (HKAS 82560) and H. subtinta (HKAS 104666).

Reference: Kevin D. Hyde1,5,8,22 · Yang Dong2,3 · Rungtiwa Phookamsak1,5,6,7 et al.

Helvella subtinta (KUN-HKAS 104666, holotype). a–g Fruiting bodies visible in natural field. h Stipitipellis. i Receptacle surface of pileus. j Asci and paraphyses. k–m Asci. n–r Ascospores. Scale bars: j–m = 50 μm, n = 20 μm, o–q = 10 μm