Scytalidium chlamydosporum S. Q. Tong & Zhi. Y. Zhang 2025, sp. nov.

5.Scytalidium chlamydosporumS. Q. Tong & Zhi. Y. Zhang, sp. nov. Fig. 3 Type. CHINA • Guizhou, Guiyang, Xiuwen County, Liuguang Town, 26.99°N, 116.44°E, soil, 5 July 2022, Shuo-Qiu Tong (holotype HMAS 354096, dried culture; ex-type CGMCC 3.28993, ibid., SQT 10) Etymology. Refers to the species that only produces chlamydospore-like cells. Description. Culture characteristics (14 days at 25 ° C): Colonies on PDA attaining 80–82 mm diam., flat, cottony, margin entire, gray-yellow (4 A 2) to pale gray (30 B 2). Reverse gray-yellow (4 A 2) to pale gray (30 B 2). Colonies on SNA fast-growing, more than 90 mm, flat, tomentose, pale gray (30 B 2). Reverse pale gray (30 B 2). Mycelium consisting of hyaline, smooth-walled, branched, septate, 1–3 μm diam hyphae. Chlamydospore-like cells yellow-brown to dark brown, oblong to globose, ellipsoidal, 0–1 - septate, thick-walled, smooth, solitary, catenate, 6–11.5 × 6–8.5 µm (avg. 8.5 × 7.1 μm, n = 30). Conidia and Arthroconidia unknown. Sexual morph unknown. Geographical distribution. Guizhou Province, China. Additional material examined. CHINA • Guizhou, Guiyang, Huaxi District, Shiban Town, 26.46°N, 106.65°E, soil, 8 July 2022, Shuo-Qiu Tong, SQT 11, ibid. SQT 12. GenBank numbers. SQT 10 – SQT 12, ITS: PV 890025 – PV 890027, LSU: PV 890032 – PV 890034. Notes. Phylogenetic analysis showed that three new isolates (SQT 10 – SQT 12) clustered in a single subclade with high supported value (100 / 1) and were closely related to S. cuboideum and S. sphaerosporum (Figs 1, 2). Morphologically, S. chlamydosporum differs from S. cuboideum by its absent arthroconidia and production of chlamydospore-like cells (Kang et al. 2010). Scytalidium chlamydosporum differs from S. sphaerosporum by its absent sexual morph and production of chlamydospore-like cells (Kang et al. 2010). Furthermore, based on a pairwise comparison of ITS, S. chlamydosporum (ex-type CGMCC 3.28993) differs from S. cuboideum (ex-isotype UAMH 676) by 10.9 % (60 / 549 bp, 21 gaps) and from S. sphaerosporum (ex-type ATCC 34392) by 12.4 % (64 / 513 bp, 28 gaps). Scytalidium chlamydosporum was isolated from soil in a pepper cultivation area and is likely to have a saprophytic lifestyle.