Description from Flora of China
Serapias falcata Thunberg in Murray, Syst. Veg., ed. 14, 816. 1784; Cephalanthera bijiangensis S. C. Chen; C. japonica A. Gray; C. platycheila H. G. Reichenbach; C. raymondiae Schlechter; Cymbidium falcatum (Thunberg) Swartz; Epipactis falcata (Thunberg) Swartz; Pelexia falcata (Thunberg) Sprengel; P. japonica Sprengel.
Plants leafy, autotrophic, 20-50 cm tall. Stem slender to somewhat robust, 4-7-leaved. Basal sheaths 3-5, 1-5 cm. Leaves elliptic, elliptic-lanceolate, or ovate-lanceolate, 5-11 × 1.5-3.5 cm, apex acuminate to obtuse. Inflorescence subdensely 5-10-flowered; rachis 3-8 cm; floral bracts usually very small, 1-3 mm and all shorter than ovary, though occasionally lower one to 12 mm and exceeding ovary. Flowers suberect, weakly spreading, yellow; pedicel and ovary straight to slightly curved, 7-15 mm. Sepals rhombic-elliptic, 12-15 × 3.5-4.5 mm, 5-veined, apex obtuse to acute. Petals similar to sepals but shorter, 8-12 × 2.5-4.5 mm, apex obtuse to acute; lip suberect, 8-9 mm, spurred at base, 2-partite; hypochile lobes erect and loosely embracing column, triangular to ovate-lanceolate, 1.5-3.5 mm, apex subacute; epichile transversely elliptic, ca. 5 × 8-9 mm, densely papillose toward apex, with 5-7 brownish orange lamellae; central 3 lamellae 0.5-1 mm tall, outer lamellae shorter; spur protruding between bases of lateral sepals, conic, sometimes slightly incurved, ca. 3 mm, apex obtuse. Column 6-7 mm, apex dilated, with 2 ovate wings; anther elliptic, ca. 2 mm. Capsule narrowly elliptic, 2-2.5 × 0.5-0.6 cm. Fl. Apr-May, fr. Aug-Sep. 2n = 34.
Cephalanthera bijiangensis, described as a species endemic to Yunnan (Acta Phytotax. Sin. 25: 472. 1987), was distinguished from C. falcata only by the length of the lowest floral bract, which exceeds the ovary. Though the floral bracts of C. falcata are frequently all short (to ca. 3 mm), several collections seen from Japan indicate that plants of this species do occasionally have a foliaceous lower floral bract that exceeds the ovary. As such, it seems unjustifiable to maintain C. bijiangensis as distinct, and it is here treated as a synonym of C. falcata, with which it agrees in other respects.
Forests, grasslands, valleys, along streams; 700-2000 m. Anhui, N Fujian, N Guangdong, N Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, W Yunnan (Bijiang), Zhejiang [Japan, Korea].