washboard
- kingdom: Animalia
- phylum: Mollusca
- class: Bivalvia
- order: Unionida
- family: Unionidae
- genus: Megalonaias
- species: Megalonaias nervosa
Chattahoochee
FloridaRock Island
IllinoisDavenport
IowaChetopa
KansasCoraopolis
Pennsylvania
United States