From the Extinction Portraits series
The Arcuate Pearly Mussel was a species of freshwater bivalve native to the United States. It became extinct because of habitat loss, most likely due to the construction of dams.
Thirty-eight species of North American freshwater mussel have been driven to extinction, and seventy-seven additional species are threatened. Little in known about these important, though perhaps uncharismatic, cleaners of our water. They are one of North America's most threatened groups of animals.