Plants terrestrial or lithophytic. Leaves 4-6, distichous; blade abaxially light green, adaxially deep green with paler margin, narrowly oblong, 10-24 × 1.6-2.7 cm, unequally bilobulate or tridenticulate at apex. Scape suberect or arching, terminating in a flower; peduncle green, 6-15 cm, with purple-red hairs; floral bract green spotted with purple-red, ovate, 1.8-3 × 1.2-1.4 cm; pedicel and ovary 3-4 mm, densely purple pubescent. Flower 6-6.5 cm in diam.; dorsal sepal white longitudinally striped with purple-brown in basal 2/3; synsepal pale green, ± veined with purple-brown; petals and lip pale green clearly flushed and veined with purple-brown; staminode pale yellow-green, with a green umbo. Dorsal sepal suborbicular, 2.5-3.5 × 2.5-3.5 cm, minutely ciliate, basal margin recurved, apex acute; synsepal subovate, 2.2-3 × 1.7-2 cm. Petals narrowly oblong, 2.7-3.9 × 0.8-1 cm, margin strongly undulate, white ciliate, apex obtuse; lip helmet-shaped; pouch ellipsoid, 2.2-2.4 × 1.5-1.8 cm. Staminode broadly obovate, ca. 1 × 1 cm, with an umbo in lower part. Fl. Sep.