Specimen ID | State | County | Locality | Year |
| Drainage name | Status |
280375
| MD | Montgomery | Cabin John Run by Seven Locks Road, beneath and near I-495 bridge crossing, W side of Bethesda | 2010 |
02070008
| Middle Potomac-Catoctin | established |
280377
| 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 |
157928
| MD | Washington | Chesapeake and Ohio Canal National Historical Park | 1999 |
02070004
| Conococheague-Opequon | collected |