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Name derivation:

“Small bags”.  Common name ‘Bladderwort’.


Utricularia Linnaeus 1753

Class Scrophulariales;  Family Lentibulariaceae


Unique “utricules” – some leaves have been greatly modified into pouches with hinged covers that can be triggered by small zooplankton such as rotifers to sweep the animal inside and trap it, providing a supply of nitrogen (as NH3) for the plant. The utricle epidermis, both inside and outside, contains a large diversity of trichomes (epidermal hairs), some of which secrete mucilaginous material -- presumably to aid in trapping prey. They also have trigger hairs, four in U. biflora, that cause the door of the trap to sweep shut (Thurston and Seabury 1975).

Non-utricular leaves are alternate on the branching stem,  highly dissected (lack a blade), and bifurcate.

The entire plant is submerged except for the floral stalk that produces several bilaterally symmetric flowers.


Freshwater lakes, often slightly acidic with low buffering capacity, as in New England USA.




Linnaeus, C.  1753.  Species Plantarum 18.

Thurston, E.L., and F. Seabury 1975. A scanning electron microscopic study of the utricle trichomes in Utricularia biflora Lam. Botanical Gazette 136:87-93.