Morphological and phylogenetic analyses reveal two new species in Conidiobolus s. s. (Conidiobolaceae, Entomophthorales) from China Author Nie, Yong https://orcid.org/0000-0001-8964-1661 Anhui Provincial Key Laboratory for Microbial Pest Control, Anhui Agricultural University, Hefei 230036, China & School of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243002, China Author Cai, Yue https://orcid.org/0000-0002-4970-9673 Department of Biological and Environmental Engineering, Hefei University, Hefei 230601, China Author Zhao, Heng https://orcid.org/0000-0003-2938-5613 Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China Author Zhou, ZhengYu https://orcid.org/0000-0001-9312-1626 School of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243002, China Author Zhao, ChangWei https://orcid.org/0009-0007-7573-346X School of Civil Engineering and Architecture, Anhui University of Technology, Ma'anshan 243002, China Author Liu, XiaoYong https://orcid.org/0000-0002-8808-010X College of Life Sciences, Shandong Normal University, Jinan 250014, China 622001@sdnu.edu.cn Author Huang, Bo https://orcid.org/0000-0001-6032-7396 Anhui Provincial Key Laboratory for Microbial Pest Control, Anhui Agricultural University, Hefei 230036, China bhuang@ahau.edu.cn text MycoKeys 2023 2023-07-05 98 221 232 http://dx.doi.org/10.3897/mycokeys.98.103603 journal article http://dx.doi.org/10.3897/mycokeys.98.103603 1314-4049-98-221 29B86571E1AB5C18B11C88BBBADD8BE1 Conidiobolus polysporus B. Huang & Y. Nie sp. nov. Fig. 3 Etymology. Polysporus (Lat.), referring to several primary conidia arising from branched primary conidiophores. Known distribution. Anhui and Shandong Provinces, China. Typification. China, Anhui Province, Ma,anshan City, Huoli Mountain, 31°67′5′′N, 118°55′37′′E , from plant debris, 3 Nov. 2021, Z.Y. Zhou and C.W Zhao , holotype BWPU 211103. Ex-type culture RCEF 7058. GenBank: nucLSU = OQ540747; EFL = OQ550510; mtSSU = OQ540745. Additional specimens examined. China , Shandong Province , Qingzhou City , Yangtianshan National Forest Park , 36°46'31"N , 118°32'56"E , from plant debris, 18 Mar 2009 , C.F. Wang , culture RCEF 4500. GenBank : nucLSU = MG272478 ; EFL = MG272476 ; mtSSU = OR100881 . Description. Colonies on PDA at 21 °C after 3 d white, reaching ca 20-23 mm in diameter. Mycelia colorless, rarely branched at the edge of colony, 8.8-13 μm wide, vegetative hyphae filamentous, frequently appearing pronouncedly vacuolated, 15-22 μm wide. Primary conidiophores often unbranched, producing a single primary conidium, without widening upward near the tip, but in some instances bifurcate thus bearing two primary conidia, or forming three conidiophores at the tip thus bearing three primary conidia, 68-270 x 11-19 μm . Primary conidia forcibly discharged, mostly globose, 42-55 x 33-45 μm , Papilla 7.5-14 μm wide, 4-12 μm long. Sometimes obovoid, up to 65 μm long. Secondary conidia arising from primary conidia, similar and smaller to the primary conidia. Microconidia rarely observed on the 2% water agar, globose to elongate ellipsoidal, 7.5-8.8 x 7.5-12.5 μm . Zygospores formed between adjacent segments after 15 days, smooth, mostly globose, less often ellipsoidal, 17.5-37 μm in diameter, with a 1-3 μm thick wall. Notes. Conidiobolus polysporus is characterized by several primary conidia (2-3) arising from conidiophores, which are similar to those in C. polytocus Drechsler and C. taihushanensis B. Huang & Y. Nie. However, C. polysporus has larger primary conidia (42-55 x 33-45 μm in C. polysporus vs. 14-29 x 12-25 μm in C. polytocus ), and forms zygospores while resting spores are absent in C. polytocus ( Drechsler 1955 ). In addition, C. polysporus differs from C. taihushanensis due to its larger primary conidia (42-55 x 33-45 μm in C. polysporus vs. 27-42 x 19-32 μm in C. taihushanensis ) and smaller zygospores (17.5-37 μm in C. polysporus vs. 34-48 x 23-40 μm in C. taihushanensis ) ( Nie et al. 2020b ). Moreover, it is distantly related to C. polytocus and C. taihushanensis in the phylogenetic tree (Fig. 1 ). Although C. polysporus is grouped with C. incongruus , it can be distinguished by its larger primary conidia (42-55 x 33-45 μm in C. polysporus vs. 18-42 x 13-37 μm in C. incongruus ) and branched conidiophore ( Drechsler 1960 ). Figure 3. Conidiobolus polysporus RCEF 7058 a colony on PDA after 3 d at 21 °C b mycelia unbranched at the edge of the colony c, d hyphae appearing pronouncedly vacuolated e, f unbranched primary conidiophores g, h branched primary conidiophpores i-k globose primary conidia l obovoid primary conidia m, n primary conidia bearing a single secondary conidium o-q microconidia arising from a conidium r, s zygospores formed between adjacent segments of the same hypha t, u zygospores. Scale bars: 100 μm ( b ); 20 μm ( c-u ).