Description from Flora of China
Cypripedium nutans Schlechter.
Plants 8-12 cm tall, with a slender, creeping rhizome. Stem erect, relatively short, 2-3 cm, glabrous, covered by 2 sheaths, with a subopposite leaf and bract at apex. Leaf and bract spreading horizontally or ascending; blade elliptic, 6-7 × 2.5-3 cm, subglabrous, apex obtuse or subacute. Inflorescence terminal, erect, 7-9 cm, with 1 flower, ebracteate; pedicel glabrous, continuously elongating at fruiting; ovary ca. 1 cm, with 3 longitudinal ridges often sparsely pubescent. Flower small; sepals and petals pale green or reddish with brown stripes; lip golden yellow ± with brown markings. Dorsal sepal elliptic or ovate-elliptic, 1.5-2 × 0.7-0.9 cm, glabrous, apex acute; synsepal similar to dorsal sepal, 1.4-1.8 × 0.7-0.9 cm, apex shallowly 2-lobed. Petals oblong-lanceolate, oblique, 1.5-1.8 × 0.5-0.6 cm, glabrous, apex acute, often ± enfolding lip; lip pouched, slightly dorsiventrally compressed, 1.2-1.5 cm, tuberculate on front surface toward mouth. Staminode broadly elliptic-oblong, ca. 6 × 4 mm, minutely papillate. Capsule ellipsoid-oblong, 1.5-1.7 × ca. 1 cm, glabrous. Fl. Jun-Jul, fr. Aug.
● Humus-rich and rocky or moist and mossy places on woody and scrubby slopes, at forest margins, or in open forests, often forming large colonies; 2300-3900 m. S Gansu, W Sichuan, SE Xizang.