Stems scrambling, terete, usually to 1 m, stout, branching. Leaves well spaced, terete, 8-18 cm × 4-5 mm, fleshy, obtuse. Inflorescence slightly longer than leaf, laxly 2-5-flowered; peduncle stout, with 3 or 4 membranous sheaths; floral bracts broadly ovate, 4-6 mm, slightly fleshy, obtuse. Flowers opening widely, 4-10 cm in diam., thinly textured, sepals and petals white, tinged with pink or purplish, lip deep purple-red, spur yellowish brown; pedicel and ovary white, 2-3 cm. Dorsal sepal broadly elliptic, ca. 2.5 × 2 cm, obtuse-rounded; lateral sepals obliquely ovate-oblong, ca. 3 × 2 cm, base adnate to column foot, apex obtuse. Petals suborbicular, large, ca. 3 × 2.7 cm, obtuse; lip spurred, 3-lobed; lateral lobes embracing column, subobovate, ca. 1.5 cm wide, rounded; mid-lobe spreading, obovate-triangular, ca. 2 cm, adaxially shortly hairy, deeply bilobed; spur conic, ca. 2 cm. Column ca. 5 mm, foot ca. 5 mm. Fl. May-Jun. 2n = 38, 40.