Transfer of Asterosporium orientale to the genus Prosthemium (Pleosporales, Ascomycota): a common coelomycetous fungus with stellate conidia occurring on twigs of Betula spp

Asterosporium orientale, described on Betula ermanii, is transferred to the genus Prosthemium, and a new combination, P. orientale, is proposed. Because of the morphological similarities, P. asterosporum originally described from twigs of B. pendula is considered as a synonym of P. orientale.