Hermatomyces pyriformis sp. nov., a novel dematiaceous hyphomycete (Hermatomycetaceae, Pleosporales) associated with medicinal plants in Yunnan Province, China Author Du, Hong-Zhi 0000-0003-0350-4530 Department of Entomology and Plant Pathology, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand & School of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, P. R. China & Innovative Agriculture Research Centre, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand & School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 611731, P. R. China hongzhi_du1012cc@163.com Author Liu, Ning-Guo 0000-0002-9169-2350 School of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang 550003, P. R. China liuningguo11@gmail.com Author Cheewangkoon, Ratchadawan 0000-0001-8576-3696 Department of Entomology and Plant Pathology, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand & Innovative Agriculture Research Centre, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand ratchadawan.c@cmu.ac.th Author Liu, Jian-Kui 0000-0002-9232-228X School of Life Science and Technology, Center for Informational Biology, University of Electronic Science and Technology of China, Chengdu 611731, P. R. China liujiankui@uestc.edu.cn text Phytotaxa 2024 2024-05-23 650 1 103 115 http://dx.doi.org/10.11646/phytotaxa.650.1.9 journal article 10.11646/phytotaxa.650.1.9 1179-3163 13216281 Hermatomyces pyriformis H.Z. Du & Jian K. Liu , sp. nov. Fig. 2 MycoBank number : MB 853034 Etymology: — pyriformis refers to pyriform-like shape of the conidiogenous cells. Holotype : — HKAS 132457 Saprobic on dead branches of Eleutherococcus nodiflorus ( Araliaceae ). Sexual morph: Undetermined. Asexual morph: Colonies on natural substrate sporodochial, superficial, scattered, circular or oval, black, shiny. Mycelium partly immersed, partly superficial, composed of subhyaline to brown, septate, branched hyphae, 1–3 µm wide. Conidiophores micronematous, indistinct, hyaline, short, smooth-walled. Conidiogenous cells monoblastic, integrated, terminal, determinate, hyaline, pyriform, smooth, or sometimes finely verruculose, 6–14 µm (x̅ = 8 µm, n = 20) long, 5–12 µm (x̅ = 8 μm, n = 20) wide at the widest part. Conidia of one type , solitary, acrogenous, lenticular, globose to subglobose or ellipsoidal in front view, muriform, constricted at septa, smooth, central cells dark brown to blackish brown, peripheral cells with 6–10 cells, brown to dark brown, rarely pale brown, ellipsoidal or oblong in side view, consisting of two adpressed halves, each half with a deep constriction, end cells light brown to brown, central cells brown to dark brown, 10–19 μm (x̅ = 14 µm, n = 30) long, 9–15 μm (x̅ = 12 µm, n = 30) wide and 8–12 μm (x̅ = 10 μm, n = 30) thick. Culture characteristics: — Conidia germinated on PDA within 24 h, and germ tubes produced from peripheral cells. Colonies growing on PDA reached 18–20 mm diam after three weeks at 25 ℃, circular, dense, margin entire, surface unsmooth with some dark brown lipid droplets, off-white in the center, light green in the middle ring, and greyish-white at the margin from above; greyish-green in the center, presented a greenish ring around, white to pale greyish at the edge from reverse. Material examined: — CHINA , Yunnan Province : Xishuangbanna Dai Autonomous Prefecture, Mengla County, Xishuangbanna tropical botanical garden Chinese Academy of Sciences. 101°15′3′′E , 21°55′38′′N , elevation 518 m , on dead branches of medicinal plant Eleutherococcus nodiflorus (Dunn) S.Y. Hu ( Araliaceae ), 10 November 2022 , H . Z . Du, S 640 ( HKAS 132457, holotype ; HUEST 23.0442, isotype ); ex-holotype living culture CGMCC 3.27462; ex-isotype living culture UESTCC 23.0441. Notes: —Phylogenetic analyses ( Fig. 1 ) showed that our two isolates ( CGMCC 3.27462 and UESTCC 23.0441) formed a distinct lineage basal to other Hermatomyces strains. Morphologically, Hermatomyces pyriformis is similar to other species in having sporodochial conidiomata and brown, muriform lenticular conidia ( Hashimoto et al . 2017 , Hyde et al . 2019 , Ren et al . 2021 , Wijayawardene et al . 2021 , Zhang et al . 2023 ). However, H. pyriformis has unique hyaline, pyriform conidiogenous cells, which are absent in other Hermatomyces species ( Koukol et al . 2018 , Ren et al . 2021 , Zhang et al . 2023 ). In addition, H. pyriformis can be distinguished from H. dimorphus , H. uniseriatus and H. truncates (three species that lack molecular data) by having pyriform conidiogenous cells and smaller lenticular conidia ( Table 3 ) while these three species have dimorphic conidia (lenticular and cylindrical). Therefore, the new species H. pyriformis is introduced based on morphology and phylogeny.