A lithophytic herb. Leaves c. 5, ligulate, rounded to obtuse, up to 70 cm long, 4.5 cm wide, green. Inflorescence arcuate, 35–70 cm long, usually 2–4-flowered; peduncle 17–35 cm, glabrous, purplish; bracts lanceolate, acute or acuminate, 3.5–5.5 cm long, 1.6–2.2 cm wide. Flowers up to 12 cm across; sepals white lined with dark maroon; petals yellow, lined and spotted maroon, + flushed with maroon in apical half; lip pale yellow, flushed pink with darker veins; staminode yellow, pedicel and ovary 4–7 cm, glabrous. Dorsal sepal ovate, acuminate, 4.5–6.4 cm long, 3–4.4 cm wide. Synsepal elliptic-ovate, acuminate, 3.7–5 cm long, 2–3.4 cm wide. Petals arcuate-dependent, linear-tapering, 10–15 cm long, 0.4–0.75 cm wide, (rarely more, up to 2 cm broad in var. platytaenium), straight or twisted in apical half. Lip pointing forwards, grooved on back. 4.5–5.9 cm long, 1.3-2.8 cm wide. Staminode convex, subcircular, truncate or incised at apex, 14 mm long, 11 mm wide, margins coarsely hairy. 2n = 26.