Plants turning black when dried, 18-65 cm tall. Tubers oblong or ovoid, 1.5-2.5 × 1-1.5 cm, fleshy. Stem erect, terete, robust, with 2 or 3 tubular sheaths and 5 or 6 leaves.

Leaf blade elliptic-ligulate or oblong-lanceolate, 2.5-12 × 1.5-4 cm, base amplexicaul, apex acuminate.

Raceme 4-19-flowered, 6-18 cm; floral bracts elliptic-lanceolate, margin ciliate, apex acuminate; ovary twisted, terete, including pedicel 2-3 cm. Sepals yellowish green, margin ciliate; dorsal sepal erect, narrowly ovate, concave, 1.3-1.5 × 0.6-0.7 cm, 5-veined, apex obtuse; lateral sepals spreading, slightly oblique, ovate-lanceolate, 1.4-1.7 × 0.5-0.6 cm, 5-veined, apex acute. Petals forming a hood with dorsal sepal, erect, white, obliquely oblong, 1.3-1.5 × ca. 0.4 cm, 3-veined, margin ciliate, unlobed, apex obtuse; lip white or yellowish white, 20-25 mm, base spurred, deeply 3-lobed above base, lobes ciliate; lateral lobes linear, 19-22 mm, outer margin comblike, with 8-10 filiform lobules; mid-lobe linear, 18-20 mm; spur pendulous, cylindric-clavate, 20-35 mm, ca. as long as or slightly shorter than ovary, thickened toward end; connective 4-5 mm wide; pollinia narrowly ellipsoid, ca. 4 mm; caudicles linear, ca. 4 mm; viscidia ovate, small; stigmas clavate. Fl. Jul-Aug. 

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