Description from Flora of China
Ammannia baccifera subf. contracta Koehne; A. baccifera subsp. viridis (Willdenow ex Hornemann) Koehne; A. discolor Nakai; A. indica Lamarck; A. vescicatoria Roxburgh; A. viridis Willdenow ex Hornemann.
Herbs, annual, 10-50[-100] cm tall. Stem with numerous, ascending branches. Leaves opposite on basal stem portion, opposite or alternate toward stem apices, narrowly elliptic or oblanceolate to linear, 5-60 × 3-10 mm, base attenuate, truncate, or subcordate. Flowers 3 to many in dense axillary cymes; pedicels subsessile, to 1 mm; peduncle absent to 1 mm; bracteoles minute, not reaching floral tube. Floral tube campanulate, tapering at base, 1-2 mm; sepals 4, ca. 0.5 mm, deltate; epicalyx absent. Petals absent. Stamens 4. Style absent to 0.3 mm, much shorter than ovary. Capsules 1-2 mm in diam., 1/4-1/2 exserted. Fl. Aug-Oct, fr. Sep-Dec. 2n = 24, 26.
Wet places, farmland. Anhui, Fujian, Guangdong, Guangxi, Hebei, Hubei, Hunan, Jiangsu, Jiangxi, Shanxi, Taiwan, Yunnan, Zhejiang [Afghanistan, Bhutan, Cambodia, India, Laos, Malaysia, Nepal, Philippines, Thailand, Vietnam; tropical Africa, Australia, Caribbean islands].