Plants 20-50 cm tall. Stems green or purplish, cylindrical, 10-25 cm long, 1-2 cm in diam., fleshy. Leaves 4-6, elliptic or oblong, 10-20 cm long, 4-7 cm wide, oblique, apex acute, base cuneate; petiole and sheath 4-10 cm long. Peduncle stout, with more than 8 sharp ridges, ca. 20-30 cm long; bracts lanceolate, 4-7 mm long, ascending or reflexed; pedicel and ovary 2-3 mm long, with 6 obtuse ridges. Flowers numerous, greenish or tinged with purple or purplish red throughout; dorsal sepal oblong, 2.5- 3.5 mm long, 1-1.2 mm wide, obtuse, revolute; lateral sepals ovate, 2.5-3 mm long, 1.5-1.8 mm wide, acute at apex, contracted at base, slightly oblique; petals linear, 2.5-3.5 mm long, 0.4-0.5 mm wide; lip ovate, 2.5-3 mm long, 3 mm wide, base truncate or rounded, close to column but usually without obvious auricles spreading backward and surrounding column, apex 3-lobed, central lobe often longest; disc with a shallow concave bottom forming a cavity near base, cavity with raised walls at its back and sides, open toward apex of lip; column 1 mm long, with 2 short wings at apex; anther yellowish white, oval, 0.3 mm long; pollinia short clavate or obliquely ovoid, apex acute; stigma slit-like. Capsules ellipsoid-cylindrical, 6-8 mm long, with rugose ridges.

TAIPEI: Hsintien, Sasaki s. n. Aug 1930. HSINCHU: Nanchung, Kawakami & Mori s .n. Jul 1906. NANTOU: Tungpu, Su 8355; Chingshuikou, Su & Chen 9066. CHIAYI: Tapan, Sasaki s .n. May 1918. KAOHSIUNG: Wangshan, Su & Chen 8601. PINGTUNG: Linungshan, Su & Chen 7997*; Chufonshan, Su 8053. TAITUNG: Lanyu Is., Sasaki s. n. Oct 1934.

Ryukyus, southern China, India, Indochina, the Philippines and through Malaysia to Australia. Taiwan, common in forests below 1,000 m throughout and on Lanyu Is.