Amblyanthus chenii (Primulaceae), a New Species and Generic Record from Xizang, China

Amblyanthus chenii (Primulaceae; Myrsinoideae) is a new species discovered growing in the understory of primeval forests in Medog County, southeast Xizang, China and is described based on morphological evidence. This is the first generic record of Amblyanthus in China. The new species is most morphologically similar to A. multiflorus. Amblyanthus chenii can be easily distinguished from other congeneric species by various morphological differences. A phylogenetic analysis based on nuclear ribosomal ITS and six plastid markers indicated that A. chenii and Amblyanthopsis burmanica form a clade that is nested within the large pantropical genus Ardisia and is sister to Ardisia subgenus Crispardisia. The close relationship among Amblyanthus, Amblyanthopsis, and Ardisia subg. Crispardisia is strongly supported by their shared synapomorphy of crenulate leaves with marginal glands.