| Specimen ID | State | County | Locality | Year | HUC Number | Drainage Name | Status |
| 232836 | PA | Erie | Elk Creek, near mouth | 1951 | 04120101 | Chautauqua-Conneaut | established |
| 232837 | PA | Erie | Presque Isle, near old police barracks-administration building | 1965 | 04120101 | Chautauqua-Conneaut | established |
| 1758631 | PA | Erie | [No locality description provided] | 1951 | 04120101 | Chautauqua-Conneaut | |
| 1758945 | PA | Erie | [No locality description provided] | 1941 | 04120101 | Chautauqua-Conneaut | |
| 1759185 | PA | Erie | [No locality description provided] | 1948 | 04120101 | Chautauqua-Conneaut | |
| 1759363 | PA | Erie | [No locality description provided] | 1941 | 04120101 | Chautauqua-Conneaut | |
| 1762358 | PA | Erie | [No locality description provided] | 1941 | 04120101 | Chautauqua-Conneaut | |
| 1763632 | PA | Erie | [No locality description provided] | 1941 | 04120101 | Chautauqua-Conneaut | |
| 1889947 | PA | Erie | [No locality description provided] | 2025 | 04120101 | Chautauqua-Conneaut | |
Citation for this information:
U.S. Geological Survey, 2025,
Butomus umbellatus: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov, Access Date: 12/17/2025