Phylogenetic Relationships of East Asian Endemic Species of Filipendula (Rosaceae-Rosoideae) as Revealed by nrITS Markers

Abstract

Phylogenetic relationships of East Asian representatives of the genus Filipendula Mill. (Rosaceae-Rosoideae) as revealed by the analyses of nrITS markers do not completely coincide with either of the existing taxonomic systems of the genus. The NW American F. occidentalis (S. Watson) Howell is a strongly isolated species which is not closely related to the Asian representatives of the genus. This study confirms close phylogenetic relations between F. tsuguwoi Ohwi (endemic to S Japan) and F. kiraishiensis Hayata (endemic to Taiwan), as well as their relationships to F. multijuga Maxim. (endemic to Honshu Island, Japan). This clade also includes the Himalayan species F. vestita Maxim. Two widely distributed species, F. camtschatica (Pall.) Maxim. and F. glaberrima Nakai, appear to be related to members of the sect. Albicomae. Filipendula formosa Nakai, a narrow endemic to S Korea, seems to be basal to this clade. Filipendula yezoensis H. Hara, endemic to Hokkaido Island, Japan, which is usually synonymized with F. glaberrima, appears to be weakly differentiated from the latter more widely distributed species.