Herbs, perennial, achlorophyllous. Roots fleshy, slender, scattered along slender rhizome. Stems leafy. Leaves several, alternate; blade spreading, plicate, or reduced to appressed sheathing bracts. Inflorescences terminal, solitary spikes, lax; floral bracts often foliaceous, large to minute, scarious distally. Flowers few-many, resupinate, sessile, showy; lip white with yellow markings, divided by median constriction, saccate, distal end with fleshy parallel adaxial lamellae; pollinaria absent; pollinia 2; viscidia absent. Fruits capsules.