Order: Alismatales
Family: Zannichelliaceae
Zannichellia palustris L., the Horned Pondweed
Synonymy: Zannichellia major (Hartm.) Boenn. ex Rchb.; Zannichellia palustris L. var. major (Hartm.) W.D.J. Koch; Zannichellia palustris L. var. stenophylla Asch. & Graebn.
Lower Taxa: none
Origin: Native
Habit: Perennial, submerged aquatic
Habitat: Fresh to Brackish Estuarine waters of Atlantic Coast, extends ocean-ward to the mesohaline; limestone waters interior
Range: Lower Delaware River counties, Coastal Strip counties; also locally distributed in limestone ponds of Warren and Sussex Counties
Frequency: Infrequent
Rank/Status: S4/G5
Wetland Status: OBL
Flowering & Reproduction: Spring to Autumn
Comments: Horned pondweed is an infrequent and often overlooked submerged aquatic found on muddy substrates in fresh tidal waters of the state. It is also distributed in a few limestone ponds in the northern counties. Its thin profile and light green color camouflages the plant. Its tidal distribution is found in habitats similar to those that support Potamogeton crispus, P. epyhydrus, P. pusillus, and Vallisneria americana.
Reference Specimen: Roadside ditch into Crammers Creek, adjacent to the Old Route 9 Bridge north of the Mullica River, Bass River Twp, Burlington Co.; JR Arsenault and MF Arsenault, 7/5/1979 CHRB107048.
Current distribution map reflects author, Chrysler herbarium specimens and Mary Hough, 1983. JRA, 9/2013
