Utricularia

Scientific name

Utricularia L.

Common names

bladderwort

Family

Lentibulariaceae

Could be confused with

Aldrovanda

Native distribution

cosmopolitan

Species commonly cultivated

Utricularia aurea Lour. (northern Australia, Asia)

U. australis R. Br. (Australia, New Zealand, Asia, Africa, Europe)

U. gibba L. (pan-tropical)

U. inflexa Forssk. (Africa, Madagascar)

U. radiata Small (North America)

U. stellaris L. (Africa, Asia, Australia)

Adventive distribution

Utricularia gibba is introduced into Europe.

Weed status

information not available

Habit

free-floating below water surface, rootless, submersed stem plant

Brief description

Perennial or annual. Submersed, free-floating or fixed by root-like rhizoids, often tangled with other plants. Leaves alternate or whorled, dimorphic: emergent leaves peltate, entire, linear, obovate, spathulate or reniform; submersed leaves usually highly dissected, with globose, bladder-like traps. Inflorescence a raceme, often supported on a whorl of inflated leaves or floats. Flowers showy, distinctive, zygomorphic; sepals 2; petals 5, fused at base, corolla 2-lipped. Dispersal by stem fragments or seeds.

Natural habitat

usually in acidic waters; terrestrial species in waterlogged or wet soils, aquatic species in ponds and other still, muddy-bottomed waters; a few species adapted to rapidly moving streams

Additional comments

A large polymorphic genus of over 200 species, most of which are terrestrial or subterranean. About 30 species are aquatic. Foliage of Utricularia may appear to be a mass of ropes; leaves may not be easily recognizable as such, or stems may look like leaves, and vice versa.