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

Fig. 7

Holotype.

China • Jiangsu Province, Nanjing, Xuanwu District, Zhongshan Sports Park, 32°05'03"N, 118°86'69"E, isolated from leaf blight of Cynodon dactylon, 3 July 2024. Holotype: CFCC 72729 is a living specimen being maintained via lyophilisation at the China Forestry Culture Collection Center (CFCC). Ex-type (ZS 19-14) is maintained at the Forest Pathology Laboratory, Nanjing Forestry University.

Etymology.

The epithet name after the Xuanwu District where the holotype of the fungus was collected.

Description.

Asexual morph on PDA: Hyphae 2–4 μm wide, subhyaline to pale brown, thin- and smooth-walled hyphae, septate, branched. Conidiophores mononematous, semi- to macronematous, septate, arising singly or frequently in groups, straight to flexuous, geniculate at upper part, unbranched, smooth, pale brown to brown, paler towards the apex, (49 –) 60–180 (– 239) × (3 –) 4–6 (– 7) μm (mean ± SD = 120 ± 60 × 5 ± 1 μm). Conidiogenous cells mono- to polytretic, proliferating sympodially, integrated, terminal or intercalary, subcylindrical, yellowish-brown, smooth to slightly verruculose, with thickened and darkened scars, (6 –) 7–11 (– 14) × 4–6 (– 7) μm (mean ± SD = 9 ± 2 × 5 ± 1 μm). Conidia straight, pale brown to dark golden brown, smooth, ellipsoidal, 2–3 - euseptate, (14 –) 18–22 (– 24) × (7 –) 8–10 μm (mean ± SD = 20 ± 2 × 9 ± 1 μm); germination mono- or bipolar. Hila 2–3 μm wide, non-protuberant, thickened and darkened. Chlamydospores and microconidia were not observed. Sexual morph not observed.

Culture characteristics.

Colonies on PDA reach 44 mm diameter after 5 days at 25 ° C in the dark. Round colonies with an entire margin, greyish-black at sporulating zone, flat and white at aging zone, cottony appearance. The centre of the reverse is greyish-green and the edge is white. On OA medium, the colonies attain up to 51 mm in diam. The edge is neat, cottony appearance, the surface of the colony is grey-black, the edge is white and the aerial hyphae are fluffy. Reverse side is greyish-black in the centre and white on the edges. On CMA medium, the colony is up to 49 mm in diam., with an irregular margin, the front and back sides are black and the surface is smooth.

Additional materials examined.

China • Jiangsu Province, Nanjing, Xuanwu District, Zhongshan Sports Park, 3 July 2024, isolated from leaf blight of Cynodon dactylon, Jia-Mei Zhao and Lin Huang, ZS 19-15; Xuanwu Lake Park, 5 June 2024, isolated from leaf blight of Cynodon dactylon, Jia-Mei Zhao and Lin Huang, XW 4-33, XW 9-10.

Notes.

Our phylogenetic analyses reveal that Curvularia xuanwuensis forms a strongly supported (100 / 1) lineage and sisters to C. australiensis. However, these species are readily distinguishable in morphology. C. australiensis differs from C. xuanwuensis by its longer conidia (15–40 μm vs. 18–22 μm), with thicker and more conspicuous conidial septa and larger conidiophores (95–205 × 3–7 μm vs. 60–180 × 4–6 μm, Laforet (2015)).