Quasipucciniastrum agrimoniae , gen. et sp. nov. on Agrimonia (Rosaceae) from China.

A new rust genus, Quasipucciniastrum , typified by Q. agrimoniae sp. nov., is proposed based on distinct morphological characters and phylogenetic placement. This genus is characterised by its uredinial ostiolar peridial cells with rough surface and sessile, multicellular teliospores with apparently thickened apical wall. Molecular phylogenetic analyses using internal transcribed spacer regions and intervening 5.8S nrRNA gene (ITS) and the large subunit (LSU) rDNA revealed that this genus is sister to the genus Cronartium (Cronartiaceae), but morphologically it is distinct from Cronartium in the sessile teliospores that are divided by vertical septa. Morphologically, Quasipucciniastrum should be compared to Pucciniastrum (Pucciniastraceae) in its multicellular teliospores, but they were phylogenetically distant.