Gastrochilus obovatifolius (Orchidaceae, Aeridinae), a new species from the Daba Mountains of Chongqing, China

<i>Gastrochilusobovatifolius</i>, a new species discovered in the Dabashan of northeast Chongqing (China), is described and illustrated. The novelty morphologically resembles <i>G.affinis</i>, <i>G.balangshanensis</i> and <i>G.heminii</i> in having a glabrous and smooth epichile. but can be distinguished by the unique obovate shape of the leaves, smaller epichile, and flower color. The results of molecular phylogenetic analysis, based on nuclear ribosome internal transcribed spacer (nrITS) and four chloroplast DNA fragments (<i>mat</i>K, <i>psb</i>A-<i>trn</i>H, <i>psb</i>M-<i>trn</i>D, and <i>trn</i>L-F) of 55 <i>Gastrochilus</i> species, support the inclusion of <i>G.obovatifolius</i> in G.sect.Microphylli, being most closely related to <i>G.balangshanensis</i> from Sichuan. The new species is a trunk epiphyte in evergreen broad-leaved forest.