Description from Flora of China
Calpidisca Barnhart; Diurospermum Edgeworth; Lentibularia Séguier; Megozipa Rafinesque; Meloneura Rafinesque; Nelipus Rafinesque; Vesiculina Rafinesque; Xananthes Rafinesque.
Herbs, perennial or annual, terrestrial, epiphytic, or aquatic, without true roots. Stems modified into rhizoids and stolons, rarely developed. Traps on rhizoids, stolons, and/or leaves, small, bladderlike. Leaves alternate or in a basal rosette, simple to many × divided, veins 1-3, unbranched, dichotomously branched, or pinnately branched. Inflorescences racemose or flowers solitary, pedunculate, usually simple, seldom branched, erect to twining, bracteate; bracts and bracteole often present, scalelike, sometimes basisolute (with base extending below point of insertion). Calyx parted from base into 2 equal or unequal lobes, lobes sometimes apically 2-parted. Corolla lower lip larger than upper lip; lower lip entire or 2- or 3(-6)-lobed, spurred, palate variously raised; upper lip entire or 2- or 3-lobed. Anther thecae confluent or distinct. Capsule adaxially loculicidal, both abaxially and adaxially loculicidal, or circumscissile, rarely indehiscent. Seeds few, many, or rarely 1 per capsule, variously appendaged.
This account is based largely on the work of P. Taylor (Kew Bull., Addit. Ser. 14: [i]-xi, 1-724. 1989), which should be consulted for a complete synonymy.
About 220 species: cosmopolitan but mostly in tropical regions, a few in N temperate regions; 25 species (four endemic) in China.