A new species of (Sonerileae, Melastomataceae) from Yunnan, China.

(Melastomataceae; Sonerileae), a species occurring in south-eastern Yunnan, China, is described as new, based on morphological and molecular data. Phylogenetic analyses, based on nrITS sequence data, showed that, except , all species sampled in formed a strongly supported clade in which two geographical lineages were recovered. The generic placement of is well supported by phylogenetic analyses and a character combination of 4-merous flowers, distinctly dimorphic stamens and the connectives basally not calcarate. Molecular divergence and morphological evidence indicate that is well separated from other members of the genus, thus justifying its recognition as a distinct species. is phylogenetically closest to , but differs markedly from the latter in stem morphology (short, obtusely 4-sided vs. long, 4-angular), habit (erect vs. creeping), leaf size (6-16.5 × 4.5-13 cm vs. 4-7.5 × 4-6.5 cm) and flower number per inflorescence (5-13 vs. 3-6).