Maryland's small, relictual population appears to have been extirpated from its small range in Garrett Co. during 1956 and 1957. The draining of Lake Koshare (near Snaggy Mountain Road) removed a pristine, isolated, cool water holdout for the species.
There are 7 records in the project database.
| GA | AL | WA | FR | CL | MO | HO | BA | BC | HA | CE | PG | AA | CV | CH | SM | KE | QA | CN | TA | DO | WI | SO | WO |