Herbs, perennial. Taproots absent, rhizomes usually with spherical or elongate, tuberous thickenings or vertical fleshy roots, rooting at nodes. Stems ascending to erect, simple or branched, terete or 4-angled. Leaves connate proximally into sheath, sessile; blade 1-veined, linear to lanceolate or elliptic, not succulent, apex acute. Inflorescences terminal, open cymes, or flowers solitary; bracts paired, smaller, herbaceous or scarious. Pedicels recurved to reflexed from base or abruptly bent downward near distal end in fruit. Flowers: perianth and androecium hypogynous; sepals 5, distinct, green, narrowly ovate to lanceolate, 3-7 mm, herbaceous, margins white, scarious, apex obtuse or acute to acuminate, not hooded; petals 5 [absent in cleistogamous flowers], white, not clawed, blade apex 2-fid to V-shaped notch 10-1/ 5 of length; nectaries adnate to base of filaments opposite sepals, circular, thickened, 2-2 1/2 times filament width; stamens 5 or 10, arising from base of ovary; filaments distinct; styles 3, capitate to clavate, 2-4.5 mm, glabrous proximally; stigmas 3, terminal or linear along adaxial surface of styles, minutely papillate (30×). Capsules ovoid, opening by 6, ± 2-3 times recoiled valves; carpophore absent. Seeds 1-3, red-brown or brown, circular to oblong or elliptic, plump or laterally compressed, tuberculate, marginal wing absent, appendage absent. x = 8.