Pegias is a monotypic genus[3] of freshwater mussels in the family Unionidae.

This genus contains the single species Pegias fabula, known commonly as the littlewing pearlymussel.

[3] This mussel has been extirpated from most streams where it once occurred, including any in the state of Alabama.

[2] The main threat to the species is bad water quality, especially due to acidic mine drainage.

Other threats include oil and gas exploration, road construction, channeling of the rivers, logging, agriculture, and pesticides.