State Status: Pennsylvania Endangered (PE)
PBS Status: Pennsylvania Endangered (PE)
Global Rank: G4
State Rank: S1
Mud-plantain (Heteranthera multiflora) is a creeping perennial herb with hairless stems. The leaves are alternately arranged, broadly heartshaped or kidney-shaped, untoothed on the margin, stalked at the base, rounded or very blunt at the tip, hairless on both surfaces, and with numerous curving veins on the fleshy blades. The flowers, appearing from July to October, are white to very pale purple and have six lobe-like segments. The male portion of the flower, the stamen, has purplish hairs, which helps to distinguish this species from the more common species Heteranthera reniformis, which has whitish hairs. The fruit is a many-seeded capsule.
Critically imperiled in the nation or state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state.
The PA Biological Survey (PABS) has assigned mud-plantain a rarity status of Endangered, based on the few populations that have been documented, its restricted state range, and the very specialized habitat.
Mud-plantain grows in intertidal marshes, mudflats, and shorelines along the lower Delaware River. The plants are subjected to daily cycles of exposure and inundation.
Flowers July - early October
In Pennsylvania, the species has been documented historically only in a few southeastern counties along the Delaware River.
The known populations have threats from exotic species, dredging and filling, and water pollution.
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.