During a survey on fungi associated with wood necroses of Prunus trees in Germany, strains belonging to the Leotiomycetes and Eurotiomycetes were detected by preliminary analyses of ITS sequences. Multi-locus phylogenetic analyses (LSU, ITS, TUB, EF-1α, depending on genus) of 31 of the 45 strains from Prunus and reference strains revealed several new taxa, including Arboricolonus gen. nov., a new genus in the Helotiales ( Leotiomycetes ) with a collophorina-like asexual morph. Seven Cadophora species ( Helotiales , Leotiomycetes ) were treated. The 29 strains from Prunus belonged to five species, of which C. luteo-olivacea and C. novi-eboraci were dominating; C. africana sp. nov., C. prunicola sp. nov. and C. ramosa sp. nov. were revealed as new species. The genus Cadophora was reported from Prunus for the first time. Phialophora bubakii was combined in Cadophora and differentiated from C. obscura , which was resurrected. Asexual morphs of two Proliferodiscus species ( Helotiales , Leotiomycetes ) were described, including one new species, Pr. ingens sp. nov. Two Minutiella species ( Phaeomoniellales , Eurotiomycetes ) were detected, including the new species M. pruni-avium sp. nov. Prunus avium and P. domestica are reported as host plants of Minutiella .