Taxonomic notes on Cimicifuga nanchuanensis (Ranunculaceae), a hitherto imperfectly known species from China

Cimicifuga nanchuanensis P. K. Hsiao (Ranunculaceae) has been regarded as an imperfectly known species. Based on critical examination of herbarium specimens and living plants we have determined that it is a morphologically distinctive species and that its geographical range is much wider than believed before, far from locally endemic to its type locality. Our cytological examination reveals the species to be a diploid (2n = 16). Our molecular phylogenetic analyses using nrDNA and cpDNA datasets confirm our morphological observations. As the generic concept and delimitation of Actaea L., in which Cimicifuga Wernisch. and Souliea Franch. are included, have also been strongly corroborated by our molecular phylogenetic analyses, here we adopt a broad Actaea and make a new combination for the species in question, i.e. Actaea nanchuanensis (P. K. Hsiao) J. P. Luo, Q. Yuan & Q. E. Yang.