Description from Flora of China
Achyranthes bidentata Blume var. longifolia Makino, Bot. Mag. (Tokyo) 12: 51. 1898.
Herbs perennial. Stem green or tinged purple, angulate or quadrangular; branches opposite. Petioles hairy; leaf blade lanceolate or broadly lanceolate, 10-20 × 2-5 cm, apex caudate. Spikes terminal or axillary; rachis white hairy. Flowers dense. Bracteoles reflexed after anthesis, acerose, ca. 3.5 mm, ciliate. Tepals shiny, lanceolate, with a midvein, apex acute. Pseudostaminodes indistinctly dentate at apex. Utricles yellowish brown, shiny, oblong, smooth. Seeds light brown, oblong.
This species is similar to Achyranthes bidentata, but differs in having leaves lanceolate or broadly so, 10–20 × 2–5 cm, caudate at the apex; bracteoles acerose, ca. 3.5 mm, ciliate at the margin; and pseudostaminodes indistinctly dentate at the apex.
Hillsides; below 1200 m. Guangdong, Guizhou, Hubei, Hunan, Jiangxi, Shaanxi, Sichuan, Taiwan, Yunnan, Zhejiang [Japan, Laos, Thailand, Vietnam].