(Lindl.) Lindl., Gen. Sp. Orchid. Pl. : 237 (1833)
Glabrous, terrestrial herb 20–40 cm high; roots stout, c. 4 mm in diameter.Pseudobulbs 2–4 × 1.5–2 cm, ovoid, oblong or cylindrical, covered when young with pale brown imbricate cataphylls, 1-leafed.Leaf with a petiole 1–2 cm long, articulated ± at the base; lamina 10–30 × 2.5–5 cm, oblong-oblanceolate or oblong-elliptic, conduplicate towards the base, coriaceous, grey-green mottled with dark green.Inflorescence erect, simple or with 1–2 short branches, fairly laxly 10–20-flowered.Pedicel and ovary 10–12 mm long; bracts lanceolate, acuminate, up to 20 mm long at base of the inflorescence.Sepals and petals greenish-white, greenish-pink or straw-coloured; lip white with 2 purple-red blotches at the base of the mid-lobe; side lobes purple-veined.Sepals 7–13 × 2–3.2 mm, linear-ligulate or narrowly oblanceolate, obtuse to acute, the dorsal sepal erect, the lateral sepals deflexed.Petals 8.5–11 × 2–4.5 mm, oblong-elliptic, oblique, obtuse.Lip 7–9 mm long, 3-lobed; side lobes erect; mid-lobe 3.5–4.2 mm long, 6–10 mm wide, broadly obovate or reniform, emarginate; disk with 2 approximate, divergent, glabrous basal keels; spur 4–5 mm long, stout, straight, bulbous at tip.Column 4–5 mm long, 2 mm wide, oblique at base or with a short foot.