1. Alternanthera sessilis (Linnaeus) R. Brown ex Candolle, Cat. Pl. Horti Monsp. 77. 1813.
莲子草 lian zi cao
Gomphrena sessilis Linnaeus, Sp. Pl. 1: 225. 1753; Alternanthera denticulata R. Brown; A. nodiflora R. Brown; Illecebrum sessile (Linnaeus) Linnaeus.
Herbs perennial, 10-45 cm tall. Stem ascending or creeping, green or somewhat tinged purple, striped, hairy, across nodes with a transverse row of hairs. Petiole 1-4 mm, glabrous or pilose; leaf blade linear-lanceolate, oblong-obovate, or ovate-oblong, 1-8 × 0.2-2 cm, glabrous or pilose, base attenuate, margin entire or slightly serrate, apex acute or obtuse. Heads 1-4, axillary, sessile, at first globose, later cylindric, 3-6 mm in diam. Flowers dense; rachis densely white hairy. Bracts and bracteoles white, glabrous, apex acuminate; bracts ovate-lanceolate, ca. 1 mm; bracteoles subulate, 1-1.5 mm. Tepals white, ovate, 2-3 mm, glabrous, with a vein, apex acuminate or acute. Stamens 3; filaments ca. 0.7 mm, connate into a cup at base; anthers oblong; pseudostaminodes subulate, shorter than stamens, margin entire, apex acuminate. Style very short; stigma shortly parted. Utricles enclosed in perianth, dark brown, obovoid, 2-2.5 mm. Seeds ovoid. Fl. May-Jul, fr. Jul-Sep. 2n = 34, 40.
Roadsides, gardens, swamps. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Zhejiang, Yunnan [Bhutan, Cambodia, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Philippines, Sikkim, Thailand, Vietnam].