Description from Flora of China
Herbs annual, 15-30 cm tall. Stem prostrate and rooting in lower part, terete, slightly fleshy, glabrous; branches erect. Stipules ovate-triangular, membranous, margin dentate-sinuate; petiole 1-5 mm, flattened; leaf blade elliptic-lanceolate, obovate-lanceolate, or obovate, 1-4 × 0.2-1 cm, papery, base acuminate, margin minutely serrulate or subentire, apex acute or attenuate. Flowers arranged into small, axillary cymes, subsessile or with short pedicel 1-5 mm, very small. Sepals erect, narrowly lanceolate, 1-2 mm. Petals pink, oblong or subspatulate, subequaling or slightly exceeding sepals. Stamens 10, free; filaments filiform, base slightly widened. Ovary subglobose; styles straight or curved. Capsule subglobose, ca. 1.8 mm in diam., longitudinally 5-grooved, 5-septicidal. Seeds oblong, minute, angular or transversely striate.
Paddy fields, moist places along ditch sides. Guangdong [India, Malaysia, Sri Lanka, Thailand; Africa, SW Asia (Iran), Europe; introduced in tropical America].