Parastagonospora yunnanensis Y. Gao, H. Gui & K.D. Hyde, in Gao, Zhong, Eungwanichayapant, Jayawardena, Hyde, Faraj, Wanasinghe & Gui, MycoKeys 109: 248 (2024)
Index Fungorum number: IF 902468; MycoBank number: MB 902468; Facesoffungi Number: FoF16258
Etymology – The specific epithet “yunnanensis” refers to Yunnan Province, where the holotype was collected.
Holotype – HKAS 128771
Saprobic on decaying stem of Loliumperenne (Poaceae). Sexual morph: Undetermined. Asexual morph: Conidiomata 35–45 µm high, 120–140 μm diam. (x̅ = 40.6 × 132.7 μm, n = 10), solitary, flattened, subglobose to irregular oval, brown to dark brown spots, immersed in the epidermis of the host, ostiolate. Conidiomata wall 4–13 µm wide (x̅ = 9 μm, n = 25), composed of brown cells of textura angularis, with an inner layer comprising hyaline cells. Conidiogenous cells (3.2–)3.5–4.7(–5.3) × (3.4–)4–5.3(–6.1) μm (x̅ = 4 ± 0.57 × 4.77 ± 0.59 μm, n = 30), hyaline, ampulliform or globose to subglobose, smooth-walled. Conidia (16.2–)18–20(–20.4) × (3–)3.2–3.7(–4) μm (x– = 19 ± 1.1 × 3.4 ± 0.24 μm, n = 35), hyaline, 0–1-septate, cylindrical to subcylindrical, rounded at apex, slightly truncate at base, guttulate, smooth-walled.
Culture characteristics – Conidia germinated on PDA within 24 hours, and a germ tube was initially produced from the ends of the conidia. Colonies on PDA reaching 20 mm in 3 weeks at room temperature (25–27 °C), regular, floccose, white from the above and light grey from the centre and below, smooth with a filamentous edge.
Material examined – China, Yunnan Province, Zhaotong City, (26°56’39″N, 103°8’53″E), on a decaying stem of Loliumperenne (Poaceae), 25 August 2022, Ying Gao, QG69A (HKAS 128771, holotype), ex-type (CGMCC 3.24527); ibid., QG69B (HKAS 128772, paratype), ex-paratype (CGMCC 3.24528); ibid., QG71A (HKAS 128773), culture (CGMCC 3.24529); ibid., QG71B (HKAS 128774), living culture (CGMCC 3.24530); ibid., Qujing City, (26°21’31″N, 103°14’13″E), on a decaying stem of Loliumperenne (Poaceae), 27 August 2022, Ying Gao, QG19A (HKAS 128799), living culture (CGMCC 3.24511); ibid., QG19B (HKAS 128800), living culture (CGMCC 3.24512).
Notes – Parastagonosporayunnanensis is introduced as a new species based on its distinct morphology and phylogenetic analysis of combined SSU, LSU, ITS, tef1-α, and rpb2 datasets. We have collected six isolates of this fungus from both the Qujing and Zhaotong regions. Parastagonosporayunnanensis is phylogenetically related to Parastagonosporaelymi (KUMCC 16-0125). Parastagonosporaelymi was introduced as a saprobic fungus from Elymusrepens in Russia, the asexual morph of Parastagonosporaelymi has not been determined (Goonasekara et al. 2019). In addition, the ITS pairwise nucleotide comparison of these species showed 18/497 bp differences (3.62%, with 2 gaps), the comparison of base pairs in LSU showed 0.36% differences (3/834 bp, without gaps), SSU, tef1-α, and rpb2 of Parastagonosporaelymi were not provided.
Figure 1 – Asexual morph of Parastagonospora yunnanensis (HKAS 128771, holotype) on a dead stalk of Loliumperenne. a, b conidiomata on the host c, d vertical section of conidiomata e conidioma wall f–h conidiogenous cells arise from the wall and develop conidia i–l conidia m germinating conidium n cultures on PDA from above o cultures on PDA from the reverse. Scale bars: 30 μm (c, d); 10 μm (e, h–m); 5 μm (f, g).