Epiphytic herbs. Stem up to 20 cm long, often curved, simple or branching, leafy, rooting at base. Leaves laterally flattened, distichously arranged, usually imbricate at base. Inflorescences arising from leaf axils, one- or two-flowered, often borne opposite one another; floral bracts linear and ovate. Flowers white, fleshy. Sepals and petals usually not widely spreading. Sepals usually free, laterals sometimes joined at base to and decurrent along spur. Petals free. Labellum firmly adnate to base of column, entire, emarginate or slightly bilobed, ecallose, pitcher-shaped and quadrangular in outline, oblong, spurred; spur globose or narrow and shallowly conical, sometimes transversely compressed, ecallose. Column foot absent; pollinia four, equal, stipe linear-clavate, 1.5–3.0 times the diameter of the pollinia, viscidium narrowly elliptic.