Paraphlomishsiwenii (Lamiaceae), a new species from the limestone area of Guangxi, China.

The indumentum of nutlets is shown to be of phylogenetic importance in previous molecular phylogenetic studies of Paraphlomis , a genus of Lamiaceae with approximately 30 species distributed mainly in southern China and Southeast Asia. Nearly half the species of Paraphlomis are known from limestone areas. In this study, we described and illustrated a new species, P.hsiwenii , from the karst mountain forests in Guangxi Zhuang Autonomous Region, China. Our molecular phylogenetic analyses revealed that P.hsiwenii is recovered in a clade consisting of species with hairy nutlets. The new species is morphologically most similar to P.pagantha from the same clade, but they differ in the morphology of lamina bases, length of pedicels and calyces, as well as the morphology of upper corolla lips.