Plants lithophytic or terrestrial. 

    Leaves 4-6, distichous; blade slightly paler and carinate abaxially, uniformly green or sometimes very obscurely tessellated dark and light green adaxially, linear, 12-19 × 0.7-1.3 cm, acute and usually minutely tridenticulate at apex.

    Scape suberect or arching, terminating in a solitary flower; peduncle brownish green, 10-14 cm, with dense purple-brown hairs; floral bract suboblong, 1.4-3.2(-3.6) cm, pubescent toward abaxial base; pedicel and ovary 3-4.2 cm, densely pubescent. Flower 6-7(-8) cm in diam.; dorsal sepal white, with a green, red-brown, or blackish brown central area in basal half; synsepal usually whitish green; petals brownish with paler margin; lip brownish with yellowish margin; staminode yellowish with orange umbo. Dorsal sepal suborbicular, 2.8-3.4(-4.5) × 2.6-3(-4) cm, puberulent abaxially, basal margin usually recurved, apical margin incurved or strongly undulate, obtuse or retuse at apex; synsepal elliptic, 2.5-3.3(-4) × 1.4-1.8 cm, puberulent abaxially. Petals spatulate or narrowly oblong, 3-4(-5) × 1-1.3 cm, adaxially pilose toward base, sparsely ciliate, undulate at margin, obtuse at apex; lip helmet-shaped, 3.5-4 cm; pouch 2-2.5 × 1.5-2 cm, outside glabrous. Staminode obovate-obcordate, 6-10 × 7-10 mm, umbonate centrally. Fl. Sep-Oct.