The subfamily Orchidoideae and the previously recognized subfamily Spiranthoideae are considered the closest allies in the natural group of the monandrous orchids because of
The Orchidoideae contain two subclades with the following tribes :
The former subfamily Spiranthoideae is now embedded as tribe Cranichideae in the clade of the Orchideoideae. It is sister to the tribe Diurideae.
The tribe Orchideae consists of the following subtribes:
The tribe Diseae consists of the following subtribes:
The polyphyletic tribe Cranichideae consists of the following monophyletic subtribes :
The tribe Diurideae consists of the following subtribes :