A Checklist with Three New Species and Two New Country Records of Begonia from Dibang Valley, Arunachal Pradesh, India

A synoptical treatment of the Begonia flora of the Dibang Valley in eastern Arunachal Pradesh, India is provided, along with the descriptions of three new species. In total, eight species of Begonia are recognized as occurring in the area, of which B. atrofusca, B. lorentzonii and B. rushforthii are new to science, while B. acetosella var. hirtifolia and and B. pseudoheydei are new records for India. A phylogenetic analysis of molecular data was performed to clarify the affinities of the treated species within the genus. Three chloroplast regions (rpl32-trnL spacer, ndhA intron and ndhF-rpl32 spacer) were sequenced and used to build a maximum likelihood phylogeny revealing that the Dibang taxa belong to two main groups of B. sect. Platycentrum.