An epiphytic or rarely lithophytic herb, often forming clumps. Leaves 4–5, linearligulate, acuminate to acute at unequally bilobulate apex, 14–42 cm long, 2.5–4 cm wide, mid-green on undersurface, purple-spotted at the base, basal margins ciliate. Inflorescence suberect to arcuate, 1- flowered; peduncle 7–24 cm long, green, often spotted purple, with long villose purple hairs; bract elliptic, obtuse, 3.7–6.5 cm long, 3–3.8 cm wide, green, spotted with maroon, glabrous. Flower 7.5–13.5 cm across; dorsal sepal green with a white margin and central glossy deep maroon areas; synsepal pale green; petals glossy reddish brown with a central maroon stripe; lip ochre, flushed with pink or reddish; staminode yellow, with a yellow or green central knob; pedicel and ovary triangular in cross-section, 3–6 cm long, ochre-coloured, densely covered with purple villose hairs. Dorsal sepal obovate, obtuse, 4.5–7 cm long, 3–4.6 cm wide, with reflexed basal margins. Synsepal adpressed to ovary, ovate, subacute, 3.8–7.6 cm long, 1.8–2.6 cm wide. Petals incurved, obovate-spathulate, retuse-emarginate, rounded at apex, 4.7–8.6 cm long, 2.5–4.6 cm wide, glossy, ciliate, purple-villose at base. Lip tapering to apex, 4–6.8 cm long, 3–3.8 cm wide. Staminode obcordate-obovate, truncate, c. 16 mm long, 14 mm wide, verrucose, hirsute, with a central glossy knob. 2n = 26.