Habit: saprophytic herbs

Stem: without leaf, with scalelike sheath or roots

Inflorescence: type: raceme

Inflorescence: position: terminal or subterminal

Sepal: free or similar

Petal: shorter or smaller than sepals, free, broader than sepals

Labellum: with sac or spur or auricles at base

Column: with wing or triangular-falcate or arm-shaped or subulate appendages, with column foot

Anther: 2-loculed

Stigma: concave

Pollinia: number: 4

Pollinia: other characteristics: granular-farinaceous, with caudicle or viscidium, without caudicle