Plants 30-58 cm tall. Rootstock tuberous, cylindric-fusiform, tapering, 2-7 × 0.5-1 cm. Stem erect, stout, with 2 or 3 tubular sheaths at base, usually 3-leaved. Leaves cauline, alternate, clustered to widely spaced, broadly elliptic, 8-13 × 1.5-5.5 cm, base contracted and clasping, apex acute. Peduncle slender to robust, with 2-4 foliaceous bracts; rachis 4-25 cm, subdensely many flowered; floral bracts linear-lanceolate, 10-25 mm, basal ones exceeding flowers, apex acuminate. Flowers faintly fragrant, yellowish green or green; pedicel and ovary cylindric-fusiform, 8-14 mm. Dorsal sepal erect, forming a hood with petals, oblong-ovate, cymbiform, 4-5.5 × 1.5-2.2 mm, glabrous, 3-veined, apex obtuse; lateral sepals reflexed, oblong-lanceolate, 4-5.5 × ca. 2 mm, glabrous, 3-veined, apex obtuse. Petals erect, obliquely ovate, 4.5-5 × 1.5-2.2 mm, apex obtuse; lip spreading to slightly pendulous, linear to ligulate, ca. 6 × 1.5 mm, entire, apex obtuse; spur pendulous, incurved, cylindric, 8-16 mm, much longer than ovary, slender, apex acuminate. Column short, staminodes small; anther locules slightly divergent; pollinia obovoid, with long caudicles and linear viscidia; rostellum rather large; stigma lobes confluent, raised, transversely elliptic, deeply 2-lobed, somewhat saddle-shaped, placed above mouth of spur. Fl. Jun-Aug.
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