New Insights into the Phylogeny of Angelica and its Allies (Apiaceae) with Emphasis on East Asian Species, Inferred from nrDNA, cpDNA, and Morphological Evidence

Abstract—

Classification of Angelica and its allies is complex and controversial, with previous phylogenetic studies restricted to examination of small numbers of taxa using only nrDNA ITS sequences. In this study, phylogenetic analyses of nrDNA ITS and ETS sequences, cpDNA sequences (rps16 intron, rps16-trnK, rpl32-trnL, and trnL-trnT), and morphological data, supplemented by observations of fruit anatomy and micromorphology, were used to ascertain evolutionary relationships and confirm generic boundaries within Angelica s.l. (including Angelica, Archangelica, Coelopleurum, Czernaevia, and Ostericum), with emphasis on its East Asian members. Most species of Angelica s.l. fall into two major, disparate clades, the Ostericum clade and the Angelica group, with the latter comprising five major lineages that are distinguished both molecularly and morphologically: Angelica s.s. (including Czernaevia), Archangelica, Coelopleurum, Glehnia, and a newly identified Littoral Angelica clade. A North American Angelica clade was also distinguished in the ITS trees. Taxonomic realignments will be required, as many species of Angelica fall outside of Angelica s.s. and four species of Angelica occur outside of the Angelica group (A. hirsutiflora, A. oncosepala, A. paeoniifolia, and A. sinensis). The Angelica s.s. clade contains predominantly East Asian species and comprises five major lineages, two of which represent plants exclusively from the eastern Himalayas; each of these five lineages can also be defined morphologically. The results obtained are significantly different from traditional treatments of Angelica s.l. and provide new insights into the phylogeny and classification of the group.