The genus Melanconis (Diaporthales) Author Jaklitsch, Walter M. Author Voglmayr, Hermann text MycoKeys 2020 63 69 117 http://dx.doi.org/10.3897/mycokeys.63.49054 journal article http://dx.doi.org/10.3897/mycokeys.63.49054 1314-4049-63-69 BC2096E6D63D5F5DA23CDFDDD3D63FA9 Melanconis itoana Tak. Kobay., Bull. Govt Forest Exp. Stn Meguro 226: 19 (1970). Type material. Holotype : Japan, Shizuoka, Fujinomiya, Mt. Fuji, on Betula ermanii , 6 Aug 1968, T. Kobayashi (TFM FPH3375; ex-type culture MAFF 410080 = LFP-M4-9 = ME8). Description. See Kobayashi (1970) and Fan et al. (2016) . Culture : Colony on MEA circular, first hyaline, forming a white outer and brown inner zone, with radial stripes; conidiomata forming mostly in the inner zone. Odour indistinct. Note. This species occurs on Betula ermanii in Japan and Betula albosinensis in China and is particularly well characterised by its long narrow fusoid conidia, which are more or less pointed at each end. It was originally described by Kobayashi (1970) in detail and the asexual morph was redescribed by Fan et al. (2016) , who gave slightly shorter measurements of conidia (12-13.5(-14) x 3.5-4(-4.5) μm ). Our measurements of conidia are (13-)14.7-17.5(-20) x (3-)3.5-4.3(-4.7) µm , l/w (3-)3.6-4.7(- 5.4) (n = 100), upon examination of the holotype, which corresponds with Kobayashi (1970) . The Chinese accessions genetically differ significantly from the ex-type culture from Japan (Fig. 1 ) and may therefore merit separation.