Pegias

Pegias
Conservation status

Critically Imperiled (NatureServe)[1]
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Unionoida
Family: Unionidae
Genus: Pegias
Species: P. fabula
Binomial name
Pegias fabula
I. Lea, 1838

Pegias is a monotypic genus[2] of freshwater mussels in the family Unionidae containing the single species Pegias fabula, known commonly as the littlewing pearlymussel. It is native to the Cumberland and Tennessee River systems in the United States, where it is present in streams in North Carolina, Kentucky, Virginia, and Tennessee.[3] It is a federally listed endangered species of the United States.

This mussel is up to 3.8 centimeters long by 1.3 wide. The outer surface of the shell is light greenish or dark yellowish, but it is often eroded off, leaving the shell chalky whitish in color.[2]

This mussel has been extirpated from most streams where it once occurred, including any in the state of Alabama. There are fewer than 12 remaining populations, most of which contain fewer than 500 individuals.[3]

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.[3]

References