Polycephalomyces bannaensis X. Zhang, N. Y. Liu, K. D. Hyde & T. C. Wen sp. nov. Fig. 5 Etymology. Reference to the Mengzhe Village, Menghai County, Xishuangbanna City, the locality where the type specimen was collected. Type. CHINA • Yunnan Province, Dai autonomous prefecture of Xishuangbanna, Menghai County, Mangunxiazhai Town, 21°58'32.33"N, 100°23'5.03"E, alt. 1237 m, 10 August 2024, Nan-Yi Liu, BN 24081002-1 (holotype: HKAS 149983). Description. Parasitic on adult of Coleoptera. Sexual morph: undetermined. Asexual morph: Hyphomycetous. Synnemata 9–33 mm in length and 0.7–1.3 mm in width, occurring either scattered or clustered on the stipe, branched, white, cylindrical, with an enlarged globose fertile head at the apex. Fertile heads 0.1–0.8 mm in width, globose to subglobose, white, covered with conidial mass. Conidiophores 15–25 µm long (x ̄ = 18.8 µm, n = 30), predominantly concentrated within the fertile head, monothetic, occurring either solitarily or in acropleurogenous whorls, and bear 1–4 phialides. Phialides 10–18.9 × 0.9–2.2 µm (x ̄ = 13.8 × 1.5 µm, n = 30), narrowly cylindrical, hyaline, smooth-walled, tapering gradually from the middle to the apex. Conidia 2.4–3.3 × 1.5–2.1 µm (x ̄ = 2.9 × 1.8 µm, n = 30), unicellular, oblong-ellipsoid to obovoid, hyaline. Habitat and distribution. On insect of Coleoptera currently known from southwestern China. Additional specimens examined. CHINA • Yunnan Province, Dai autonomous prefecture of Xishuangbanna, Menghai County, Mangunxiazhai Town, 21°58'32.33"N, 100°23'5.03"E, alt. 1237 m, 10 August 2024, Xing-Can Peng, BN 24081002-2 (paratype: HKAS 149954). Notes. Phylogenetically, Polycephalomyces bannaensis is sister to Po. tengchongensis (97 % ML / 1 PP, Fig. 1). Polycephalomyces bannaensis is distinct in having longer synnemata (9–33 mm long) and oblong-ellipsoid to obovoid conidia, while Po. tengchongensis has shorter synnemata (18.7 mm long) and globose conidia. Additionally, P. bannaensis parasitizes coleopteran insects, whereas Po. tengchongensis infects fungi (e. g., Perennicordyceps cf. elaphomyceticola). The PHI test results (Fig. 2) revealed no significant recombination relationships between Po. bannaensis and its phylogenetically related taxa (Φw = 0.2105). Based on molecular phylogenetic analyses and morphological observations, we propose that these two species are distinct from each other and introduce our collections as a new species.

Published as part of Zhang, Xian, Peng, Xing-Can, Wei, De-Ping, Wang, Yi, Norphanphoun, Chada, Hongsanan, Sinang, Xie, Ning, Liu, Zhong-Liang, Mapook, Ausana, Kang, Ji-Chuan, Saichana, Natsaran, Hyde, Kevin D. & Wen, Ting-Chi, 2026, Reappraisal of the phylogenetic relationships of hirsutella-like fungi across Ophiocordycipitaceae and Polycephalomycetaceae (Hypocreales, Sordariomycetes), and the description of seven new species, pp. e 171084 in IMA Fungus 17 on page e171084, DOI: 10.3897/imafungus.17.171084