Herbs annual, 20-50 cm, prostrate. All parts streaked with linear white raphides. Petiole poorly defined, 2-10 mm; leaf blade elliptic, lanceolate, or spatulate, 1-2.5 cm × 4-10 mm, both surfaces with many white raphides, base attenuate, apex obtuse or subacute. Inflorescences mostly sessile, apparently axillary, densely umbel-like. Flowers 5-20. Pedicel 3-5 mm. Tepals 5, green (to red), ovate, 1.5-2 mm, apex acute. Stamens 5, ca. 1 mm; filaments flattened and dilated at base. Carpels 5; styles short. Mericarp reniform, mostly spiny tuberculate, sometimes also some smooth, surrounded by persistent tepals. Seeds black, smooth, minutely pitted. Fl. summer-autumn, fr. winter.

Collections from Iran and Pakistan with winged mericarps have been described as var. alata M. G. Gilbert.

Open, sandy habitats, often near the sea;; low elevations. Hainan [Afghanistan, India, Pakistan, Thailand, Vietnam; tropical and subtropical Africa; introduced in North America (SE United States)].