Herbs, annual. Taproots slender. Stems prostrate to erect, branched, terete to finely ridged. Leaves opposite or in whorls of 4, not connate, petiolate; stipules 2 per node, silvery, lanceolate to triangular-ovate, margins entire or irregularly cut, apex acuminate to aristate; blade 1-veined, spatulate or oblanceolate to ovate or elliptic, not succulent, apex obtuse, sometimes mucronate. Inflorescences terminal or axillary, dense or lax cymes; bracts paired or absent. Pedicels erect. Flowers: perianth and androecium perigynous; hypanthium minute, cup-shaped, not abruptly expanded distally; sepals distinct, green, lanceolate to elliptic or ovate, often keeled, 1-2.5 mm, herbaceous, margins white, scarious, apex acute, ± hooded, ± awned; petals often fugacious, 5, white, blade apex emarginate; nectaries between filament bases; stamens 3-5; filaments shortly connate distally around ovary; style 1, obscurely 3-branched, filiform, 0.1-0.3 mm, glabrous proximally; stigmas 3, linear along adaxial surface of style branches, papillate (30×). Capsules ovoid to spherical, opening by 3 incurved or twisting valves; carpophore present. Seeds ca. 8-15, whitish, ovoid to lenticular or triangular, laterally compressed to angular, papillate or granular, marginal wing absent, appendage absent. x = , 8, 9.