Orchideae is a tribe of orchids in the subfamily Orchidoideae. It has been divided into two subtribes, Orchidinae and Habenariinae. The subtribe Orchidinae alone contains about 1,800 species.[1] However, although some phylogenetic studies have established the monophyly of the subtribes, the generic boundaries are unclear, with many genera as traditionally circumscribed being paraphyletic or even polyphyletic.[2] Species of genera such as Habenaria and Platanthera have been placed into both subtribes.[3] A 2017 molecular phylogenetic study found that both subtribes did form clades, but did not formally recognize Habenariinae, because of missing genera and uncertainty over generic boundaries.[1] The Asian species of Orchideae, in particular, have been subject to repeated changes of generic placement from 2012 onwards.[3][2][4][5][6][1]
Genera included in a 2017 molecular phylogenetic study are listed below. As noted above, some generic boundaries remain uncertain; Habenaria in particular is not monophyletic.[1]