Phylogenetic and taxonomic evidence reveal Roussoella bambusicola sp. nov. (Pleosporales, Dothideomycetes) from Yunnan Province, China Author Chen, Xue-Mei 0009-0004-8631-0735 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, P. R. China & Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand & Center of Excellence in Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand e3396023108@gmail.com Author Suwannarach, Nakarin 0000-0002-2653-1913 Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand & Center of Excellence in Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand suwan_461@hotmail.com Author Du, Tian-Ye 0000-0003-2105-1803 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, P. R. China & Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand fungitianyed@163.com Author Lu, Wen-Hua 0000-0001-7283-7596 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, P. R. China & Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand & Center of Excellence in Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand reuven0319@gmail.com Author Elgorban, Abdallah M. 0000-0003-3664-7853 Center of Excellence in Biotechnology Research (CEBR), King Saud University, Riyadh, Saudi Arabia aelgorban@ksu.edu.sa Author Alfagham, Alanoud T. 0000-0001-9008-3679 Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia aalfaghom@ksu.edu.sa Author Tibpromma, Saowaluck 0000-0002-4706-6547 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, P. R. China saowaluckfai@gmail.com Author Karunarathna, Samantha C. 0000-0001-7080-0781 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, P. R. China & National Institute of Fundamental Studies, Kandy, Sri Lanka samanthakarunarathna@gmail.com text Phytotaxa 2024 2024-10-30 670 2 97 108 https://doi.org/10.11646/phytotaxa.670.2.2 journal article 306657 10.11646/phytotaxa.670.2.2 d71c9933-4d74-4c34-80dc-72e2bd49387e 1179-3163 14519487 Roussoella bambusicola X.M. Chen, S. Tibpromma & Karun. , sp. nov. FIGURE 2 Index Fungorum number : IF902581; Facesoffungi number : FoF 16483 Etymology: From Latin, cola means dwelling on, and Bambusa is the genus name of bamboo. Holotype : GMB-W1009 Saprobic on decaying bamboo culms. Sexual morph : Undetermined. Asexual morph : Stromata raised, ellipsoidal or globe, occasionally irregular, visible as black on the host surface. Conidiomata 170–550 × 120–220 μm ( x = 449 × 169.5 μm, n = 15) scattered or gregarious immersed in the stromata, ellipsoidal, dark brown. Conidiomatal wall up to 70 μm wide comprised several layers of cells of textura angularis , with hyaline to dark brown. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 2.5–24 × 2–4.5 μm ( x = 12 × 3 μm, n = 40), lining the inner wall layer of the pycnidium, ampulliform or lageniform to subcylindrical, slightly curved, hyaline, smooth-walled. Conidia 4–5.5 × 2.5–3 μm ( x = 4.9 × 2.8 μm, n = 40), oblong or ellipsoidal, hyaline to light brown or yellowish brown, aseptate with two guttules, smooth or rough-walled. Culture characters: Conidia germinated on PDA within 24 h. 20 mm diam. after four weeks at 25–27 ° C , rounded, with even margin, white, with raised center, fluffy from above, white at the margin, black at the center, ringlike from below. Mycelium is superficial, branched, septate, white, smooth. Material examined: China , Yunnan Province , Lijiang City , Shigu Town , on dead culms of bamboo, 15 September 2023 , X. M . Chen, LS118 ( GMB-W1009 , holotype ), ex-type living culture GMBCC1032 ; ibid . LS118-1 ( GMB-W1010 isotype ), ex-isotype living culture GMBCC1034 . Notes: Our new strain Roussoella bambusicola forms the sister clade with R. guttulate ( MFLUCC 20-0102) with 91% ML , 1 PP statistical support ( Figure 1 ). Based on a pairwise nucleotide comparison of ITS , LSU , tef 1-α, and rpb 2 sequences, R. bambusicola deviates from R. guttulate ( MFLUCC 20-0102) by 70/543 bp (12.89%, without gaps) for ITS , 6/876 bp (0.68%) for LSU , 37/935 bp (3.95%) for tef 1-α, and 84/1065 bp (7.88%) for rpb 2. The asexual morph of Roussoella guttulate ( MFLUCC 20-0102) is undetermined, so the morphological comparison is unavailable ( Zhang et al . 2020 ). However, the asexual morphic features of Roussoella bambusicola resemble Roussoella in having ampulliform or lageniform to subcylindrical, hyaline conidiogenous cells, and oblong or ellipsoidal, aseptate, hyaline to brown conidia ( Liu et al . 2014 ; Dai et al . 2017 ; Hyde et al . 2023 ). Therefore, we introduce our strain as a new species in Roussoella .