Subtribe Orchidinae (Orchidaceae, Orchidoideae) are a nearly cosmopolitan taxon of terrestrial orchids, comprising about 1800 species in 47 to 60 genera. Although much progress has been made in recent years of phylogenetics of Orchidinae, considerable problems remain to be addressed. Based on molecular phylogenetics, we attempt to illustrate the phylogenetic relationships and discuss generic delimitation within Orchidinae. Seven DNA markers (five plastid and two nuclear), a broad sampling of Orchidinae (400 species in 52 genera) and three methods of phylogenetic analysis (maximum likelihood, maximum parsimony and Bayesian inference) were used. Orchidinae s.l. are monophyletic. Satyrium is sister to the rest of Orchidinae s.l. Brachycorythis and Schizochilus are successive sister to Asian-European Orchidinae s.s. Sirindhornia and Shizhenia are successive sister to clade formed by Tsaiorchis-Hemipilia-Ponerorchis alliance. Stenoglottis is sister to the Habenaria-Herminium-Peristylus alliance. Habenaria, currently the largest genus in Orchidinae, is polyphyletic and split into two distant clades: one Asian-Australian and the other African–American–Asian. Diplomeris is sister to Herminium s.l. plus Asian-Australian Habenaria. We propose to recognize five genera in the Ponerorchis alliance: Hemipilia, Ponerorchis s.l., Sirindhornia, Shizhenia and Tsaiorchis. Splitting Habenaria into two genera based on morphological characters and geographical distribution may be the least disruptive approach, and it is reasonable to keep Satyrium in Orchidinae.

Five new species (Gastrochilus yei, Gastrochilus minimus, Luisia simaoensis, Taeniophyllum xizangense, Tuberolabium subulatum) and two newly recorded species (Cleisostoma tricornutum, Luisia inconspicua) of Vandeae (Orchidaceae) from China are described and illustrated. Gastrochilus yei is similar to G. affinis and G. nepalensis, but differs from them by having an epichile not lobed, the apex of the hypochile not bilobed, and a tine on the apex of the leaf. Gastrochilus minimus is similar to G. acinacifolius, but can be distinguished from the latter by having a flabellate epichile that is densely hirsute on the adaxial surface and an inconspicuous central cushion; in addition, the hypochile of G. minimus has a keel that extends to the apex of the epichile. Taeniophyllum xizangense is similar to T. stella and T. radiatum, but it is distinguished from them by having much bigger flowers, inflorescences densely covered with short-bristly hairs, papillae on the external surface of sepals, and bigger triangular-ovate viscidium. Luisia simaoensis is similar to L. magniflora and L. ramosii, but can be easily distinguished from them by having lateral sepals longer than dorsal sepals and petals, lip with irregular and waved margins, and lip with bilobed apex. Luisia inconspicua is moved from Gastrochilus to Luisia based on phylogenetic analyses of plastid matK sequence data. Tuberolabium subulatum is similar to T. carnosum, but it can be easily distinguished from the latter by having an inflorescence much shorter than the leaves, yellow sepals and petals, and many small papillae outside the lip lobes.

Four new species of Gastrochilus (Vandeae, Orchidaceae) — G. menglaensis, G. tsii, G. wenshanensis and G. labrosus—are here described and illustrated, based on materials collected from China and Laos. Additionally, Gastrochilus minutiflorus is for the first time recorded in China and G. brevifimbriatus is reduced to a synonym of G. fargesii.