Platanthera yadongensis (Orchidaceae, Orchideae), A New Species from Tibet, China

Abstract Platanthera yadongensis , a new species of orchid from Yadong, Tibet, China, is described and illustrated. This new species is close to P. deflexilabella in sharing ciliate sepals, two long and outstretching stigmatic lobes, and naked and involute viscidia, but it differs from the latter in having bracts much longer than the ovaries in lower flowers, lips shorter than the sepals, spurs longer than the lips but much shorter than the ovaries and pedicels, and anther thecae slightly divergent towards the base. A key to all known species with two outstretching stigmatic lobes from China is provided.