Appalachian monkey-face pearly mussel, Appalachian monkeyface
Theliderma sparsa, the Appalachian monkey-face pearly mussel or Appalachian monkeyface, is a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels.
This species is endemic to western Virginia and eastern Tennessee in the Appalachia region, in the Southeastern United States.
It is critically endangered due to pollution of the rivers in which it lives. Being a detritivore, the mussel absorbs the pollutants which contaminate the river as it feeds.
There are two to three populations remaining. In the Clinch River of Virginia there is a small, isolated population. A population in the upper Powell River in Tennessee is nearly gone. These occurrences may not be viable. All other occurrences have been extirpated.
