Plants annual, herbaceous, glabrate to glandular-puberulent, often densely so in inflorescences, not glaucous. Stems prostrate and spreading, branched, rooting at some nodes, 20-60+ cm. Leaves opposite; stipules persistent, divided into 3-5 subulate to fili-form segments, 1-2 mm; petiole 2-15 mm; blade orbiculate to reniform, 0.5-2.5 cm × 5-25 mm, base cordate to rounded, apex rounded to acute. Inflorescences axillary and terminal, mostly open, 5-15+-flowered cymes. Pedicels shorter to longer than subtending bracts at maturity. Flowers: sepals with weak veins arcing outward at midsection and ± confluent apically, lanceolate to ovate (herbaceous portion similar), 2-4(-5) mm, ± equal, apex acute to acuminate (herbaceous portion similar), not hooded, glabrous or with ± sessile glands; petals 2-fid for 3/ 4+ their total length, 2-3 mm, 2- 3 times as long as sepals, lobes 1-veined, vein unbranched, linear, trunk absent, base abruptly tapered, apex rounded to acute. Seeds dark reddish brown, snail-shell-shaped, 1-1.5 mm; tubercles prominent, rounded. 2n = 24 (Africa, India), 36 (South America, Taiwan). Flowering year-round. Lawns, gardens, disturbed areas; 10-30 m; introduced; Fla., Ga., La., Miss.; Mexico; West Indies; Central America; South America; introduced in tropical areas of the Old World.