Multigene phylogeny and morphology reveal three new species of Cytospora isolated from diseased plant branches in Fengtai District, Beijing, China Author Jia, Aoli https://orcid.org/0009-0004-0265-5454 State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China Author Chen, Baoyue Key Laboratory for Silviculture and Conservation of the Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Lu, Hongyan Key Laboratory for Silviculture and Conservation of the Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Xing, Yu Key Laboratory for Silviculture and Conservation of the Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Li, Bin Key Laboratory for Silviculture and Conservation of the Ministry of Education, Beijing Forestry University, Beijing 100083, China Author Fan, Xinlei https://orcid.org/0000-0002-4946-4442 State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing 100083, China xinleifan@bjfu.edu.cn text MycoKeys 2024 2024-01-18 101 163 189 http://dx.doi.org/10.3897/mycokeys.101.116272 journal article http://dx.doi.org/10.3897/mycokeys.101.116272 1314-4049-101-163 B3407E32182D54A38A90C118F97C94A5 Cytospora euonymina X.L. Fan & C.M. Tian, Persoonia 45: 21 (2020) Fig. 5 Description. Sexual morph : not observed. Asexual morph : Conidiomata pycnidial , immersed in the bark, scattered, producing black area on bark, erumpent through the surface, with multiple locules. Conceptacle absent. Ectostromatic disc honey to dark mouse grey, conspicuous, circular to ovoid, 200-500µm in diam, with one ostiole per disc. Ostiole in the centre of the disc, black, conspicuous, 80-200 μm diam. Locules numerous, subdivided frequently by invaginations with common walls, 400-750 µm in diam. Conidiophores borne along the locules, hyaline, unbranched or occasionally branched at the base or in the middle, thin-walled, 8-12 x 1.5-2 (av. = 10 +/- 2.1 x 1.8 +/- 0.3, n = 50) μm , embedded in a gelatinous layer. Conidiogenous cells enteroblastic, phialidic. Conidia hyaline, elongate-allantoid, smooth, aseptate, 5-7 x 1-2 (av. = 6 +/- 0.5 x 1.5 +/- 0.3, n = 50) µm . Culture characteristics. Cultures on PDA are initially white, irregular, lacking aerial mycelium, fast growing up to 5 cm diam. after 3 d. Colonies pale white to light salmon after 30 d, pycnidia distributed sparsely over the medium surface. Figure 5. Cytospora euonymina from Salix babylonica (BJFC CF20230403) A, B habit of conidiomata on branch C transverse section through conidiomata D longitudinal section through conidiomata E, F conidiophores and conidiogenous cells G conidia. Scale bars: 500 µm ( A ); 200 µm ( B ); 100 µm ( C, D ); 10 µm ( E-G ). Materials examined. China , Beijing City , Fengtai Distinct , Qianling Mountain scenic area, 39°51'12.28"N , 116°5'17.74"E , from branches of Salix babylonica , 12 Apr 2023 , A.L. Jia & X.L. Fan (BJFC CF20230403, living culture CFCC 59444; BJFC CF20230404, living culture CFCC 59479) . Notes. Cytospora euonymina was isolated from Euonymus kiautschovicus in Shanxi Province, China ( Fan et al. 2020 ). It is characterised by having pycnidia covered by the darkened cuticle. Lin et al. (2023b) reported this species from leaves of Euonymus japonicus. In this study, two isolates grouped together with C. euonymina in ML and BI trees (ML/BI = 98/1). Therefore, they were identified as C. euonymina . Additionally, CFCC 59444 and 59479 extends its host range which were isolated from branches of Salix babylonica in the current study.