Abstract
Fresh collections, type studies and molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, rpb2, tef1 and tub2 sequences were used to evaluate the boundaries of Cucurbitaria in a strict sense and of several related genera of the Cucurbitariaceae. Two species are recognised in Cucurbitaria and 19 in Neocucurbitaria. The monotypic genera Astragalicola, Cucitella, Parafenestella, Protofenestella, and Seltsamia are described as new. Fenestella is here included as its generic type F. fenestrata (= F. princeps), which is lecto- and epitypified. Fenestella mackenzei and F. ostryae are combined in Parafenestella. Asexual morphs of Cucurbitariaceae, where known, are all pyrenochaeta- or phoma-like. Comparison of the phylogenetic analyses of the ITS-LSU and combined matrices demonstrate that at least rpb2 sequences should be added whenever possible to improve phylogenetic resolution of the tree backbone; in addition, the tef1 introns should be added as well to improve delimitation of closely related species.