Habit: epiphytic herbs

Stem: with scalelike sheath or roots

Leaf: characteristics: sheathing or noding at base

Leaf: position: in two rows

Inflorescence: position: laterally on stem

Inflorescence: other characteristics: unbranched

Sepal: lateral sepals adnate to column foot or labellum forming a mentum

Labellum: 5-lobed

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

Pollinia: number: 4

Pollinia: other characteristics: with caudicle or viscidium, with stipe

Viscidium:shape: ovate