Orchideae is a tribe of orchids in the subfamily Orchidoideae. It is the largest tribe, containing more than 1,700 species. It has been divided into two subtribes, Orchidinae and Habenariinae. However, although 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. Species of genera such as Habenaria and Platanthera are placed into both subtribes, so a clear assignment of all genera to subtribes is not possible as of March 2018[update].
The Asian species of Orchideae, in particular, have been subject to repeated changes of generic placement from 2012 onwards.Prairie White Fringed Orchid (Platanthera leucophaea)
Genera include:Anacamptis, Bartholina, Benthamia, Bonatea, Brachycorythis, Centrostigma, Chamorchis, Cynorkis, Dactylorhiza, Diplomeris, Dracomonticola, Galearis, Gennaria, Gymnadenia, Habenaria, Hemipilia, Herminium, Himantoglossum, Holothrix, Megalorchis, Neobolusia, Neotinea, Oligophyton, Ophrys, Orchis, Pecteilis, Peristylus, Physoceras, Platanthera, Platycoryne, Ponerorchis, Pseudorchis, Roeperocharis, Schizochilus, Serapias, Sirindhornia, Stenoglottis, Steveniella, Thulinia, Traunsteinera, Tsaiorchis, Tylostigma, Veyretella
Genera included in a 2014 molecular phylogenetic study are listed below, together with subfamily clades into which their species were placed. Four genera were split between the two subfamilies.Bonatea – Habenariinae Dactylorhiza – Orchidinae Galearis (including Neolindleya) – Orchidinae Gennaria – Habenariinae Gymnadenia – Orchidinae Habenaria – Habenariinae Hemipilia (including Hemipiliopsis) – Orchidinae Herminium (including Androcorys, Porolabium) – Habenariinae, Orchidinae Ophrys – Orchidinae Orchis – Orchidinae Pecteilis – Habenariinae Peristylus – Habenariinae, Orchidinae Platanthera (including Smithorchis) – Habenariinae, Orchidinae Ponerorchis (including Amitostigma, Neottianthe) – Habenariinae, Orchidinae Pseudorchis – Orchidinae Serapias – Orchidinae Sirindhornia – Orchidinae Tsaiorchis – Orchidinae