| Ecosystem | Type | Status | Ref. |
|---|---|---|---|
| Black Sea | Sea/Bay/Gulf | native | 45714 |
| Caspian Sea | Lake | native | 39702 |
| Danube | River (basin) | introduced | 52471 |
| Dnieper | River (basin) | native | 59043 |
| Don | River (basin) | native | 58293 |
| Kuban River | River (basin) | native | 58296 |
| Marmara | Lake | native | 92840 |
| Palearctic | Zoogeographic realm | endemic | 4696 |
| Rhine | River (basin) | introduced | 88692 |
| Vistula | River (basin) | introduced | 52518 |
| Volga | River (basin) | native | 58297 |