Annual or perennial herbs, usually found in lakes and damp places. Stem (stolons) monomorphic or dimorphic, filiform, terete and branched. Leaves either rosulate at the base of inflorescence or alternate, opposite or verticillate on the stolons, ± dichotomously divided into capillary segments, with or without single or fasciculate setulae. Bladders (traps) hollow, ovoid-globose, stalked with lateral, terminal or basal mouth. Peduncle usually simple, sometimes branched, filiform, erect or twining, with or without sterile bracts (scales), few - many flowered; pedicel usually short, terete, often reflexed or recurved in fruit; bracts persistent, basifixed, medifixed or variously produced below the point of attachment. Sepals 2-lobed, ± equal, free or ± united at the base, persistent; upper lobe usually entire, lower lobe usually emarginate. Corolla yellow, violet or purple variously shaded or white or rarely blue or red, 2-lipped; upper lip 2 or more lobed, entire; lower lip 1-2 or 5-lobed, spurred and with gibbous palate. Stamens 2; filaments usually curved. Ovary ovoid or globose; style short; stigma unequally 2-lipped, lower lip usually much larger than the upper which may be obscure or obsolete. Fruit ± globose, indehiscent or dehiscent by longitudinal slits, dorsiventral or lateral valves, pores or circumcissile. Seeds 1-many, variously shaped and sculptured.