Taxonomic reintroduction of Taphrinaviridis (Taphrinales, Ascomycota) associated with Alnusalnobetula as one of five well defined European species colonizing alders.

Phylogenetic analysis of four DNA regions (ITS, LSU, mtSSU and tef1α ) supported the existence of five European Taphrina species which colonise Alnus in Europe. In addition to previously well-defined species, T.viridis is, for the first time recognised, by molecular study as a species related to T.sadebeckii . Analysis of publicly available sequences of barcoding regions suggested that T.viridis is only associated with A.alnobetula and no other Taphrina species colonize this host tree. Symptomatic, morphological, and physiological characterisation of T.viridis are provided together with the key for identification of Alnus associated Taphrina species in Europe and North America.