Niesslia curvispora Ming. Y. Zhang & Zhi. Y. Zhang 2026, sp. nov.

Niesslia curvispora Ming. Y. Zhang & Zhi. Y. Zhang sp. nov. Fig. 2 Type. China • Shanxi, Taiyuan, Yingze Park 37.85°N, 112.56°E, soil, 17 May 2025, Zhi-Yuan Zhang (holotype HMAS 354201, dried culture; culture ex-type CGMCC 3.29401, ibid., ZY 25.001). Etymology. The epithet “ curvispora ” refers to its curved conidia. Description. Culture characteristics (14 days at 25 ° C): Colony on PDA reaching 24–27 mm diam. thick, white, margin entire, reverse similarly coloured. Colony on OA reaching 27–29 mm diam. flat, grey, margin entire, reverse similarly coloured. No growth of observed on SNA. Mycelium consisting of hyaline, smooth-walled, branched, septate, 1–3 μm diam. hyphae. Sporulation abundant and phalacrogenous. Phialides usually monocillium-like with moderately thick-walled 1–2.5 μm wide basal portion, sometimes percurrently proliferating with a twisted or spiral apex and sometimes ending with a sterile vesicle, (37 –) 45–64 μm. Conidia adhering in slimy heads, aseptate, hyaline, smooth- and thin-walled, elongated-cylindrical, gradually tapering towards ends, hardly truncate at base, curved, 6.5–11.5 × 1.5–2.5 μm (av. 9.1 × 2.6 μm, n = 30). Chlamydospores and sexual morph not observed. Geographical distribution. Shanxi Province, China. Additional material examined. China • Shanxi, Taiyuan, Yingze Park 37.85°N, 112.56°E, soil, 17 May 2025, Zhi-Yuan Zhang, ZY 25.002. • Shanxi, Taiyuan, Taiyuan Zoo 37.91°N, 112.59°E, soil, 17 May 2025, Zhi-Yuan Zhang, ZY 25.003. Notes. Phylogenetic analysis showed that three new isolates (ZY 25.001 –25.003) clustered in a single subclade with high support (100 / 1, Fig. 1). Morphologically, Niesslia curvispora shares curved conidia with N. dimorphospora and N. rhizomorpharum (Gams 1971; Gams et al. 2019). However, N. curvispora differs from N. dimorphospora by its shorter phialides (45–64 μm vs. 55–85 μm) and the shape of conidia (elongated-cylindrical vs. ellipsoidal) (Gams 1971; Gams et al. 2019). Additionally, N. curvispora differs from N. rhizomorpharum by the shape and size of its conidia (elongated-cylindrical, 6.5–11.5 × 1.5–2.5 μm in N. curvispora vs. elongate ellipsoidal, 4–7 × 1.5–2.0 μm in N. rhizomorpharum) (Gams et al. 2019). Phylogenetically, N. curvispora is related to a clade having N. hepworthiae, N. libertiae, N. neoexosporioides, N. nieuwwulvenica, N. phragmiticola and N. pseudoexilis (Fig. 1). However, N. curvispora differs from these species by its shorter phialides and curved conidia (Crous et al. 2021; Crous et al. 2022 a, b, 2023; Crous 2025). In addition, based on a pairwise comparison of ITS, LSU, TEF 1, TUB and ACT, N. curvispora (ex-type ZY 25.001) differs from N. hepworthiae (ex-type CBS 153518) by 7.9 % (47 / 588, 16 gaps) in the ITS, 2.2 % (19 / 846, two gaps) in the LSU, 68.8 % (633 / 920, 443 gaps) in the TEF 1, 27.8 % (119 / 428, 44 gaps) in the TUB and 33.9 % (106 / 312, 56 gaps) in the ACT; from N. libertiae (ex-type CBS 153519) by 9.9 % (60 / 601, 24 gaps) in the ITS, 2 % (17 / 843, one gap) in the LSU, 71.1 % (622 / 874, 485 gaps) in the TEF 1, 24.8 % (90 / 362, 34 gaps) in the TUB and 31.7 % (89 / 280, 24 gaps) in the ACT; from N. neoexosporioides (ex-type CBS 146810) by 6.3 % (40 / 627, 17 gaps) in the ITS, 1.8 % (16 / 846, two gaps) in the LSU, 25.4 % (107 / 421, 37 gaps) in the TUB and 29.1 % (88 / 302, 28 gaps) in the ACT; from N. nieuwwulvenica (ex-type CBS 148943) by 4.4 % (25 / 561, seven gaps) in the ITS, 1.3 % (11 / 805, one gap) in the LSU, 66.1 % (578 / 874, 376 gaps) in the TEF 1, 30.9 % (119 / 385, 44 gaps) in the TUB and 24.7 % (63 / 255, 20 gaps) in the ACT; from N. phragmiticola (ex-type CBS 149682) by 22.4 % (125 / 556, 66 gaps) in the ITS, 5 % (42 / 838, two gaps) in the LSU, 65.5 % (584 / 891, 415 gaps) in the TEF 1, 27.5 % (112 / 407, 42 gaps) in the TUB and 35.1 % (101 / 287, 45 gaps) in the ACT; from N. pseudoexilis (ex-type CBS 148333) by 24.6 % (151 / 613, 93 gaps) in the ITS, 6.5 % (52 / 800, one gap) in the LSU, 24.7 % (99 / 400, 42 gaps) in the TUB and 70.3 % (457 / 650, 390 gaps) in the ACT.