A morphological and molecular survey of Japanese Melampsora species on willows reveals a new species and two new records

During morphological and molecular phylogenetic studies of Melampsora species on willows, one novel species, Melampsora salicis-reinii sp. nov., and two new records, M. ribesii-viminalis and M. ribesii-purpureae, are described from Japan. Melampsora salicis-reinii on Salix reinii was characterized by its amphigenous telia and ellipsoid urediniospores with echinulate spines on a rugose surface. Phylogenetic results using the rDNA ITS region (complete ITS1, 5.8S rRNA gene and ITS2) supported morphological elucidation, and both morphological and molecular evidences supported M. salicis-reinii as a new species. In addition, M. ribesii-viminalis was identified on S. pet-susu and S. sachalinensis, and M. ribesii-purpureae was recognized on S. integra. These two Melampsora species were reported as new records in Japan for the first time.