Utricularia L., Sp. Pl. 18. 1753. Gen. Pl. ed. 5: 11. 1754; DC., Prodr. 8: 3. 1844; Clarke in Hook. f., Fl. Brit. Ind. 4: 328. 1885; Jena in Rech. f., Fl. Iran. 58: 1. 1969; Taylor in Tutin et al., Fl. Europ. 3: 296. 1972, in Polhill, Fl. Trop. East Aft. 1. 1973, in Kew Bull. Add. Ser. 14. 1989.
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.
A large genus with 214 species, distributed throughout the world, represented in Pakistan by 3 species.
Utricularla vulgaris L., Sp. Pl. 18. 1753.
Stewart reported this taxon from Pakistan. However it appears that it does not occur in our area and the material belongs to Utricularia australis R.Br. Utricularia australis and Utricularia vulgais have frequently been confused. These two species can be differentiated on the basis of following characters. Utricularia australis: Leaves with 2-primary segments; capillary leaf segments with setulae arising from the apex of the short teeth; palate of corolla gla-brous; inner distal half of the spur of the corolla with glands on both dorsal and ventral surfaces. Utricularia vulgaris: Leaves with 2-4 primary segments; capillary leaf segments with setulae directly arising from the margins, without any teeth; palate of corolla pubescent; inner distal half of the spur of the corolla with glands on dorsal surface only.