Phylogeny and taxonomy of the genera of Erysiphaceae, part 6: <i>Erysiphe</i> (the “ <i>Microsphaera</i> lineage” part 2)

This is the sixth contribution in a series devoted to the phylogeny and taxonomy of powdery mildews. This part includes our third treatment of the species of the genus <i>Erysiphe</i>. It continues the previous contribution on the phylogenetic-taxonomic assessment of the species belonging to the "<i>Microsphaera</i> lineage." Since this is a large lineage, we have split the treatment of the "<i>Microsphaera</i> lineage" into two parts. Phylogenetic trees based on rDNA are supplemented by sequences of additional markers (<i>CAM, GAPDH, GS, RPB2</i>, and <i>TUB</i>). The "<i>Erysiphe trifoliorum</i> complex" is a challenging group that belongs to the "<i>Microsphaera</i> lineage." Adequate clarification of this complex will be possible when additional worldwide multilocus sequence analyses are performed. The new species <i>Erysiphe acetosae, E. acmisponis, E. lathyrina, E. salmoniana</i>, and <i>E. santalicola</i> are described, and the new combinations <i>E. biuncinata</i> and <i>E. pavoniae</i> are introduced. Specimens of several species have been sequenced for the first time, particularly North American species, such as <i>Erysiphe caryae, E. ceanothi, E. juglandis-nigrae</i>, and <i>E. ravenelii. Erysiphe syringae</i> is lectotypified and 15 species names are epitypified in order to provide ex-epitype reference sequences. For other species, non-ex-type reference sequences are proposed for phylogenetic-taxonomic purposes. Ex-type sequences for <i>Erysiphe baptisiicola, E. sesbaniae, Microsphaera sydowiana, M. umbilici</i>, and <i>Oidium pavoniae</i> have been retrieved.