The Cumberland monkeyface pearly mussel or Cumberland monkeyface, scientific name Quadrula intermedia, is a species of freshwater mussel in the family Unionidae, the river mussels. This aquatic bivalve mollusk is native to Tennessee and Virginia in the United States, where it occurs in the Duck and Powell Rivers. It is a federally listed endangered species. This mussel has been extirpated from the Elk River. There is still a population in the Powell River, and the population in the Duck River appears to be viable.