Annual or perennial herbs, aquatics or plants usually of wet places, predominantly insectivorous; leaves alternate or in basal rosettes. Often dimorphic in aquatic representatives with submerged leaves usually finely divided, and bearing insectivorous bladders of complex structure. Flowers bracteate, pedicels of some each with a pair of bracteoles, in scapose racemes or solitary on a scape, bisexual zygomorphic, the calyx 2-5 lobed or divided, the segments open or imbricate, the corolla gamopetalous, 5 lobed, inbricate, bilabiate, the lower lip saccate or spurred, with the palate very variable in form;  stamens 2, with 2 staminodes sometimes produced, anthers 1 celled, dehiscing longitudinally, no disc produced; pistil 1, ovary superior, unilocular, the carpels 2 the placentations free central, the ovules numerous on or often sunken into a globose placental mass, anatropus, the style 1, stigma 2 lobed sessile, fruit a capsule, seeds minute with poorly differentiated embryo and no endosperm.