Curvularia nanjingensis Lin Huang, Jia-Mei Zhao & D. W. Li, 2025

Zhao, Jia-Mei, Peng, Chuan-Xu, Zhang, Qiu-Yue, Li, De-Wei & Huang, Lin, 2025, Five novel species of Curvularia (Pleosporales, Pleosporaceae) isolated from turfgrasses, MycoKeys 125, pp. 279-305 : 279-305

Curvularia nanjingensis Lin Huang, Jia-Mei Zhao & D. W. Li sp. nov.

Fig. 6

Holotype.

China • Jiangsu Province, Nanjing, Jianye District, Yuzui Wetland Park , 31 ° 97 ' 13 " N, 118 ° 65 ' 54 " E, isolated from leaf blight of Cynodon dactylon , 29 Aug 2024. Holotype : CFCC 72723 is a living specimen being maintained via lyophilisation at the China Forestry Culture Collection Center ( CFCC). Ex-type (YZ 25-10 - 2 - 1) is maintained at the Forest Pathology Laboratory, Nanjing Forestry University.

Etymology.

The name refers to the city, Nanjing where the holotype was collected.

Description.

Asexual morph on PDA: Hyphae 3–4 μm wide, subhyaline to pale brown, thin- and smooth-walled, septate, branched. Conidiophores mononematous, semi- to macronematous, septate, arising singly or frequently in groups, straight to flexuous, geniculate towards the apex, unbranched, smooth-walled, subhyaline to dark brown, (113 –) 163–279 (– 384) × (3 –) 4–6 μm (mean ± SD = 221 ± 58 × 5 ± 1 μm). Conidiogenous cells mono- to polytretic, proliferating sympodially, integrated, terminal or intercalary, subcylindrical to irregularly swollen, yellowish-brown, smooth, 6–14 (– 18) × 4–6 μm (mean ± SD = 10 ± 4 × 5 ± 1 μm). Conidia straight or curved, elliptical to lunate, smooth, 2–3 - euseptate, median cells unequally enlarged, pigmentation intensified to dark brown and median septum thickened, apical and basal cells subhyaline to pale brown, (13 –) 16–20 (– 22) × (7 –) 9–13 (– 14) μm (mean ± SD = 18 ± 2 × 11 ± 2 μm); germination mono- or bipolar. Hila 2–3 μm wide, inconspicuous to slightly conspicuous, slightly thickened and darkened. Chlamydospores present, intercalary, smooth-walled, solitary or grouped in chain, subglobose to oblong, 8–12 (– 13) × (6 –) 7–9 (– 10) μm (mean ± SD = 10 ± 2 × 8 ± 1 μm, n = 20). Microconidia not observed. Sexual morph: Undetermined.

Culture characteristics.

Colonies on PDA reach 46 mm diam. after 5 days at 25 ° C in the dark. Round colonies, regular margin, flat without bulge, greyish-black at sporulating zone, white at aging zone. The centre of the reverse is greyish-green and the edge is yellowish-white. On OA medium, the colonies are up to 51 mm in diam., with regular margin, smooth surface, black on both front and reverse sides. On CMA medium, the diameter is up to 49 mm and the morphology is similar to that on OA medium.

Additional materials examined.

China • Jiangsu Province, Nanjing, Jianye District, Yuzui Wetland Park , 29 August 2024, isolated from leaf blight of Cynodon dactylon, Jia-Mei Zhao and Lin Huang, YZ 25-10 - 2 - 2, YZ 25-10 - 2 - 3 .

Notes.

Phylogenetically, Curvularia nanjingensis is allocated to a strongly supported lineage (100 / 0.98) in Curvularia and related to C. chiangraiensis and C. simmonsii (Fig. 2 ). However, C. chiangraiensis can be easily distinguished from C. nanjingensis by its smaller conidiophores (50–150 × 2–7 μm vs. 163–279 × 4–6 μm, Yasanthika et al. (2023)). Curvularia simmonsii differs from C. nanjingensis by its longer conidia (21–27 μm vs. 16–20 μm, Ferdinandez et al. (2021)). Additionally, C. nanjingensis can produce chlamydospores, while this feature is not observed in C. chiangraiensis and C. simmonsii . Furthermore, C. chiangraiensis and C. simmonsii have only been sporadically reported. The former has been reported to be isolated from soil; the latter was isolated from the leaf lesions of Panicum maximum in Sri Lanka ( Ferdinandez et al. 2021; Yasanthika et al. 2023).

Figures

Figure 2. Phylogenetic relationships of Curvularia strains isolated from turfgrasses and closely-related taxa of Curvularia, based on Maximum Likelihood analyses using concatenated ITS + GAPDH + tef 1 sequences. Numbers above the branches indicate ML bootstrap values (left, ML ≥ 50 %) and Bayesian posterior probabilities (right, BPP ≥ 0.90). T = Ex-type strain.

Figure 6. Curvularia nanjingensis (YZ 25-10 - 2 - 1, type). A – C. Colony on PDA (A), OA (B) and CMA (C), respectively in 5 days after incubation at 25 ° C; D. Sporulation on PDA; E – K. Conidia, conidiogenous cells and conidiophore; L. Chlamydospores; M – N. conidia. Scale bars: 100 μm (D); 10 μm (H – M).