Habit: epiphytic herbs

Rhizome: with fibrous roots

Leaf: characteristics: 2, petiolate

Inflorescence: type: raceme

Inflorescence: other characteristics: rachis pubescent or zigzagged flexuose or winged

Sepal: lateral sepals dilated or saccate at base or bent downward, lateral sepals spreading or oblique or reflexed or connivent

Labellum: with sac or spur or auricles at base

Column: with wing or triangular-falcate or arm-shaped or subulate appendages, without column foot

Rostellum: ligulate or ovate or U-shaped or deltoid

Pollinia: number: 4

Fruit:type: capsule

Fruit: other characteristics: with persistent column