A terrestrial or lithophytic herb. Leaves 5–8, narrowly oblong-elliptic to elliptic, tridenticulate at acute apex, up to 15 cm long, 3.5–4.1 cm wide, sparsely ciliate at base, mottled pale and darker green above, pale green below. Inflorescence 1- (rarely 2-) flowered, erect, up to 36 cm long; peduncle 20–27 cm long, purple, finely densely purple-pubescent; bract ovate, acute, 2–2.4 cm long, 1.4 cm wide, green, pubescent. Flower 8–9.5 cm across; dorsal sepal white, greenish at base, veined with purple; synsepalum pale yellow-green, veined green and lightly flushed with purple; petals pale green below, purple above with darker veins and dark maroon spots on upper margin and sometimes towards upper margin in basal half; lip rich purple-maroon to pale green heavily flushed deep maroon; staminode pale green, veined with darker green; pedicel and ovary 5–6.7 cm long, pale green, tinged purple on ribs, finely purple-pubescent. Dorsal sepal ovate, apiculate, 3.9–5 cm long, 4.3–5.5 cm wide, pubescent on outer surface. Synsepal narrowly ovate, acute, 3.2–3.5 cm long, 1.5–1.6 cm wide. Petals deflexed, more or less straight, ligulate, obtuse, 4.9–6 cm long, 1–1.6 cm wide, ciliate, sparsely pubescent at base. Lip 4.5 cm long, 2–2.5 cm wide, warty on incurved side-lobes, apical margin sparsely ciliate. Staminode lunate, 9–10 mm long, 10 mm wide; apical lateral teeth falcate, acute. 2n = 38.