Erect to pendent epiphytic herbs. Stem simple or branching, compressed, stout, covered by leaf-sheaths. Leaves distichous, sessile, articulate, narrow, ligulate, apex truncate, unequally bilobed, or acute, distant. Inflorescence lateral, racemose, many-flowered. Flowers with sepals and petals white flushed rose-pink or greenish yellow, labellum purple or white. Sepals and petals spreading, petals narrower than sepals. Labellum spurred, lacking ornaments, trilobed, side lobes triangular, midlobe oblong or rhomboid, obtuse, margin sometimes erose; spur with a mouth closed by a high transverse wall at base of midlobe. Column cylindric, broadened at base, foot not distinct; pollinia four, in unequal pairs, the smaller half in each pair detaching as a free flat disc, stipe broadened upwards, about twice the length of diameter of pollinia; viscidium ovate.