Leaves 4–12, usually distichous, up to 25 cm long, 2–6 cm wide near the apex, obovate or spathulate with a sheathing base, unequally 2-lobed at the apex with the lobes rounded or acute; lamina fleshy or leathery, dark green, often with black dots.
Sepals and petals 20–45 × 4–8 mm, all narrowly lanceolate, acuminate, often with margins recurved so that they look even narrower; dorsal sepal erect; lateral sepals and petals soon becoming reflexed.
Inflorescences to 25 cm long, arching or pendent, 2–12-flowered. Peduncle to 10 cm long with 2–3 tight sheaths; rhachis slightly zigzag.
Epiphytic herb; stem woody, erect or pendent, to 20 cm long but usually shorter; roots 5–6 mm in diameter, grey.
Lip deflexed, 20–45 × 5–10 mm, lanceolate, acuminate; spur 12–24 cm long, straight or slightly curved.
Flowers in 2 rows, 1.5–3.5 cm apart, white, sometimes tinged with pinkish or brown.
Fruit to 20 cm long, narrowly cylindrical.
Bracts to 9 mm long, triangular, acute.
Column 6–8 mm long; rostellum porrect.
Pedicel and ovary 3.5–7 cm long.