State Status: N
PBS Status: Pennsylvania Threatened (PT)
Global Rank: G5
State Rank: S2
Did You Know?
One of the distinguishing traits of this species is that the bladders are not seen.
Horned bladderwort (Utricularia cornuta) is a perennial with very small, slender leaves that are usually hidden in the substrate or submerged in shallow water. The leaves may be difficult to locate but are noteworthy for possessing bladders that trap and digest tiny animals. The plant has yellow flowers (appearing in summer) that have a sharp-pointed spur and are borne on an erect stalk up to 30cm in height The fruit is a capsule with many small seeds. When flowers are absent, the plant is difficult to locate and identify.
Imperiled in the nation or state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state.
The horned bladderwort has been given a proposed status of Threatened on the Plants of Special Concern in Pennsylvania list by the Pennsylvania Biological Survey, based on the relatively few historical and recent records that have been documented in the state. Additional field work is needed in order to justify this status, as recent field work has shown that the species may be more frequent than previously believed.
The species grows in shallow water or wet peaty substrate in ponds, bogs, seepages, and along shorelines.
Flowers July - August
It occurs mainly in the glaciated northeastern counties in Pennsylvania.
Conservation Status Map
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org.
- NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available at https://www.natureserve.org/explorer
- Pennsylvania Natural Heritage Program. 2018.
- Rhoads, A.F. and W.M. Klein, Jr. 1993. The Vascular Flora of Pennsylvania. American Philosophical Society, Philadelphia, Pennsylvania. Rhoads, A.F. and T.A. Block.
- 2007. The Plants of Pennsylvania: An Illustrated Manual. 2nd edition. University of Pennsylvania Press, Philadelphia, Pennsylvania.