Four new species of Dothideomycetes (Ascomycota) from Para Rubber (Hevea brasiliensis) in Yunnan Province, China Author Xu, Rui-Fang https://orcid.org/0000-0003-1207-8254 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, China & Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, Thailand Author Karunarathna, Samantha C. https://orcid.org/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, China & School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand Author Phukhamsakda, Chayanard https://orcid.org/0000-0002-1033-937X Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, Thailand Author Dai, Dong-Qin https://orcid.org/0000-0001-8935-8807 Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, China Author Elgorban, Abdallah M. https://orcid.org/0000-0003-3664-7853 National Institute of Fundamental Studies (NIFS), Kandy, Sri Lanka Author Suwannarach, Nakarin https://orcid.org/0000-0002-2653-1913 Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia Author Kumla, Jaturong https://orcid.org/0000-0002-3673-6541 Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia Author Wang, Xiao-Yan https://orcid.org/0009-0009-6430-3637 Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand & Center of Excellence in Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai, Thailand 527010142@qq.com Author Tibpromma, Saowaluck https://orcid.org/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, China saowaluckfai@gmail.com text MycoKeys 2024 2024-03-22 103 71 95 http://dx.doi.org/10.3897/mycokeys.103.117580 journal article http://dx.doi.org/10.3897/mycokeys.103.117580 1314-4049-103-71 0C28E032647A557A9563F8DDF53D2D47 Pseudochaetosphaeronema xishuangbannaensis R.F. Xu & Tibpromma sp. nov. Fig. 6 Etymology. The name refers to the location "Xishuangbanna, Yunnan, China", where the holotype was collected. Holotype. ZHKU 23-0107. Description. Saprobic on a dead branch of Hevea brasiliensis . Sexual morph : Ascomata 270-410 μm high, 370-480 μm diam., (x‾ = 350 x 420 μm , n = 5), solitary, scattered, immersed, globose to subglobose, uni-loculate, black. Peridium 40-90 μm wide, thin-walled, composed of several layers of small, brown to pale brown cells of textura intricata. Hamathecium comprises 2-3 μm wide, numerous, dense, filiform, unbranched, hyaline, cellular pseudoparaphyses. Asci 130-180 x 25-35 μm (x‾ = 155 x 32 μm , n = 20), 8-spored, bitunicate, obovoid, short distinct pedicel with conical end, apex rounded with a minute ocular chamber. Ascospores 30-50 x 10-20 μm (x‾ = 42 x 13 μm , n = 30), hyaline, fusiform, with pointed ends, 3-5-septate, larger upper third cell, constricted at the septa, guttulate, thick-walled, with mucilaginous sheath, the sheath constricted at the middle. Asexual morph : Undetermined. Figure 6. Pseudochaetosphaeronema xishuangbannaensis (ZHKU 23-0107, holotype ) a-c appearance of ascomata on host substrate d section of an ascoma e peridium f pesudoparaphyses g-j asci m-t ascospores u ascospore stained with Indian ink k, l colonies on PDA (k-front and l-reverse view). Scale bars: 200 µm (d) ; 100 µm (e) ; 50 µm (f-j) ; 10 µm (m-t) ; 20 µm (u) . Culture characteristics. Colony on PDA, colonies slow growing on 28 °C, umbonate, filiform, smooth, edges brown, from above, brown, dark brown on reverse side. Material examined. China , Yunnan Province , Xishuangbanna on a dead branch of Hevea brasiliensis , 12 September , 2021, Rui-Fang Xu , XSBNR-41 (ZHKU 23-0107, holotype ); ex-type ZHKUCC 23-0804, ZHKUCC 23-0805 . GenBank numbers. ZHKUCC 23-0804 = ITS: OR853097, LSU: OR922338, SSU: OR922344, tef 1-α: OR966286; ZHKUCC 23-0805 = ITS: OR853098, LSU: OR922339, SSU: OR922345, tef 1-α: OR966287. Notes. In the phylogenetic analyses, Pseudochaetosphaeronema xishuangbannaensis clusters with P. lincangensis with 99% ML and 1.00 PP support (Fig. 3 ). Morphologically, P. xishuangbannaensis differs from P. lincangensis in having longer asci (130-180 μm vs. 90-145 μm ), 3-5-septate ascospores with sheath constricted at the central septum and brown to dark brown colonies, while P. lincangensis has ascospores with a normal sheath in a circle, 1-septate ascospores with obtuse ends and colonies off-white from the forward edge, orange in reverse. Pseudochaetosphaeronema xishuangbannaensis shares similar morphologies with P. chiangraiense , but can be differentiated by having the peridium with the cells of textura intricate , larger ascomata (270-410 x 370-480 μm vs. 190-255 x 190-200 μm ), longer asci (130-180 μm vs. 50-110 μm ), larger (30-50 x 10-20 μm vs. 20-45 x 15-30 μm ) and 3-5 septate ascospores with a sheath constricted at the central septum and brown to dark brown colonies. Pseudochaetosphaeronema chiangraiense has textura angularis peridium, ascospores surrounded by a normal sheath in a circle, 1-septum, obtuse ends, from above, greenish-grey in the middle and pale brown at the margin, yellowish-brown on the reverse side ( Boonmee et al. 2021 ). In addition, P. xishuangbannaensis formed a different lineage with P. chiangraiense (Fig. 3 ). Therefore, P. xishuangbannaensis is described as a new species, based on phylogenetic analyses and morphological comparison.