Illinois pondweed
- kingdom: Plantae
- phylum: Tracheophyta
- class: Liliopsida
- order: Alismatales
- family: Potamogetonaceae
- genus: Potamogeton
- species: Potamogeton illinoensis
- Belmopan
Cayo
Belize- Charlemagne
- Lavaltrie
- Longueuil
Quebec
Canada- San José
Petén
Guatemala- Benito Juarez
Mexico City- Anenecuilco
- Ciudad Ayala
Morelos
Mexico- Spanish Fort
Alabama- Paragould
Arkansas- Eustis
- Leesburg
- McGregor
- Whiskey Creek
Florida- Oquawka
Illinois- Columbia City
- Culver
- Fowler
- Gary
- Shorewood Forest
Indiana- Clear Lake
Iowa- Havre de Grace
- Perryville
Maryland- Amherst Center
- Cambridge
- Somerville
Massachusetts- Le Center
Minnesota- Buffalo
- Green Island
- Herkimer
- Mohawk
- Troy
- Watervliet
New York- Klamath Falls
Oregon- Hemlock Farms
Pennsylvania- Brushy Creek
Texas- Mead
Washington- Washington, D. C.
Washington, D.C.- Green Bay
- Oconomowoc
Wisconsin
United States