Specimen ID | State | County | Locality | Year |
| Drainage name | Status |
280451
| MD | Montgomery | Potomac River, upstream and downstream ends of Plummers Island and Swainson Island area, just E of I-495 crossing, W side of Bethesda | 2010 |
02070008
| Middle Potomac-Catoctin | established |
280446
| MD | Montgomery | Potomac River, upstream and downstream ends of Plummers Island and Swainson Island area, just E of I-495 crossing, W side of Bethesda | 2010 |
02070008
| Middle Potomac-Catoctin | established |