Lihengia: A new genus of Asteraceae distinct from Dubyaea

A new genus, Lihengia, is established for two species presently treated within Dubyaea, which is proved to be paraphyletic in the present study, even after exclusion of Lihengia. Dubyaea is a genus of about 15 species endemic to the Sino-Himalayan region that are treated within subtribe Crepidinae of tribe Cichorieae within Asteraceae. Stebbins suggested that Dubyaea may contain species representing direct ancestors of several widerspread genera in tribe Cichorieae, thus making phylogenetic reconstruction challenging. We tested the monophyly of Dubyaea using a molecular phylogeny reconstructed from ITS and five plastid fragment sequences (petD, psbA-trnH, 5 ' trnL((UAA))-trnF, rpl32-trnL((UAG)), trnQ((UUG))-5 ' rps16) and sampling comprising Dubyaea and related species within the tribe Cichorieae. We resolved Dubyaea species within at least two separate clades of tribe Cichorieae. Most species of Dubyaea occurred in subtribe Crepidinae, while Dubyaea sect. Amoena was placed in subtribe Lactucinae. Based on our findings, we erect Lihengia as a new genus to accommodate the species of D. sect. Amoena, and, consequently, we propose two new combinations. We discuss the morphological and cytological support for the new genus.