Helvella yongpingensis T.S. Li & Q. Zhao, 2025

Li, Tai-Shun, Yang, Yan-Yan, Yu, Feng-Ming, Li, Cui-Jin-Yi, Xu, Rong-Ju, Yang, Hu-Hua, Zhou, De-Qun & Zhao, Qi, 2025, Two new species of Helvella (Helvellaceae, Pezizales) from Southwestern China, Phytotaxa 684 (2), pp. 219-231 : 225-228

Helvella yongpingensis T.S. Li & Q. Zhao , sp. nov. FIGURE 3

Index Fungorum number: IF903277

Diagnosis: Pileus shallowly cupulate to cupulate when young, irregularly lobed to discoid when mature, dark grey hymenium with irregular grey and white patches, pubescent receptacle surface dark grey, pubescent terete stipe white to slightly yellowish white. Asci 240–320 × 14–18 μm, ellipsoid ascospores 18–21 × 11–12.5 μm.

Etymology:— The specific epithet is proposed because of the type locality being Yongping County of the fungus.

Holotype:— CHINA, Yunnan Province, Dali Bai Autonomous Prefecture, Yongping County, Jinguangsi Provincial Nature Reserve , alt. 2,450 m, under Castanopsis orthacantha forest, 24 Jul. 2024, Tai-Shun Li 364 ( HKAS 145324 ).

Apothecia 2–6 cm high, 1–3 cm broad, shallowly cupulate to cupulate when young, irregularly lobed to discoid when mature; hymenium grey to dark grey with irregular grey and white patches, becoming brown when dried; receptacle surface densely pubescent, dark grey when fresh, becoming grewish brown when dried. Stipe 1–4 cm long, 3–7 mm in diam., terete, or sometimes slightly sulcate, internally solid, densely pubescent, white or slightly yellowish white, becoming light brown when dried. Medullary excipulum 250–310 μm in thickness, composed of 2.5–6 μm in diam., hyaline, thick-walled cells of textura intricata, J-. Ectal excipulum 150–220 μm in thickness, comprised of hyaline to pale brown cells of textura angularis, terminal cells 19–33 × 10–18 μm, J-. Stipitipellis 150–310 μm, comprised of hyaline cells of textura angularis, terminal cells 15–27 × 9–13 μm, J-. Asci 240–320 × 14–18 μm, 8- spored, pleurorhynchous, subcylindrical to clavate. Paraphyses 3–5 μm in diam., filiform, slightly exceeding the asci, apex enlarged, 6–8 μm in diam., brown, blue in cotton blue, J-. Ascospores [50/4/2, in H 2 O] (17–) 18–21 (–22.5) × 11–12.5 (–13) μm [ Q = 1.48–1.82, Q = 1.61 ± 0.08], ellipsoid, smooth-walled, with one large oil drop in central when mature.

Habitat:— Scattered or gregarious on the ground in the Castanopsis orthacantha forest.

Material examined:— CHINA, Yunnan Province, Dali Bai Autonomous Prefecture, Yongping County, Jinguangsi Provincial Nature Reserve, alt. 2450 m, under Castanopsis orthacantha forest, 24 Jul. 2024, Tai-Shun Li 365 ( HKAS 145325).

Notes:— Helvella yongpingensis is characterized by its cupulate to discoid apothecia, irregular grey and white patches of hymenium, pubescent receptacle surface, terete or sometimes slightly sulcate stipe and ellipsoid ascospores. In our phylogenetic analysis, H. yongpingensis was nested into the xiaohuipan lineage and was a sister branch of H. xiaohuipan ( Fig. 1 ). In morphological characteristics, H. yongpingensis can be confused with H. xiaohuipan , with cupulate apothecia with densely pubescent, grey to dark grey receptacle surface and white to yellowish white stipe (Mao et al. 2023). However, H. yongpingensis and H. xiaohuipan differ in the irregular grey-white patches in the hymenium (present in the former and absent in the latter), the length of the stipes (1–4 cm vs. 1.2–1.8 cm), and the Width of the paraphyses apex (6–8 μm vs. 4.5–6 μm) (Mao et al. 2023).

Figures

FIGURE 1. Maximum likelihood phylogenetic tree generated from combined ITS, nrLSU, tef-1α, and hsp90 sequenced dataset.Maximum likelihood bootstrap (ML-BP) ≥ 70% and Bayesian posterior probabilities (BI-PP) ≥ 0.90 are indicated above the nodes.Specimen vouchers are noted after the species names. New samples collected in this study are indicated in red. Type specimens are in bold.

FIGURE 3. Helvella yongpingensis. a–c Typical mature specimens (a HKAS 145324, holotype; b–c HKAS 145325); d Receptacle surface; e Stipitipellis; f Asci and paraphyses; g–i Asci; j–r Ascospores. Scale bars: a–c = 2 cm; d–i = 100 μm; j–r = 10 μm.