Plants 20-45 cm tall. Rhizomes distinct, terete, 5 mm thick. Pseudobulbs 2-5 cm apart, short clavate, 2-3 cm long. Leaves 4 or 5, suberect, linear or linear oblanceolate, 25-35 cm long, 1.5-3 cm wide, apex acuminate, base narrowed, thinly coriaceous, 3-nerved. Scapes 15-25 cm tall, with 3 or 4 tubular scales in lower portion; flowering portion 3-6 cm long, more or less densely flowered; bracts lanceolate, membranaceous, nearly hyaline, glabrous, caducous; pedicel and ovary 1.2 cm long. Flowers white; glabrous; dorsal sepal oblong, 1 cm long, 4-5 mm wide, acute at apex, slightly contracted at base, 3-nerved; lateral sepals similar to dorsal one but longer and more or less oblique; petals obovate, 8-9 mm long, 56 mm wide, rounded and apiculate at apex, narrowed at base, 3-nerved; lip 3-lobed, 6-7 mm long, spurred, lateral lobes ovate, 2-3 mm long, central lobe obcordate, 4-5 mm long, 4 mm wide, retuse at apex, disc with 2 erect ridges at base, spur 6-7 mm long, cylindrical, obtuse at apex; column 5 mm long, connate with base of lip and forming a tube; anther white, ovate, 2 mm long; pollinia elongate clavate, 2 mm long, merging into caudicles and attached to an ellipsoid viscidium; stigma solitary; rostellum slender, less than 1 mm long, undivided.

PINGTUNG: Linungshan, Su & Chen 8584*; Chingshuiying, Su 9353.

Java, Sumatra, Malaysia, southern China (Hainan) and the Philippines. Taiwan, only in the south, in moist, mossy forests at 1,000-1,500 m, rather rare.