Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Fluted Kidneyshell and Slabside Pearlymussel

We, the U.S. Fish and Wildlife Service (Service), designate critical habitat for the fluted kidneyshell (Ptychobranchus subtentum) and slabside pearlymussel (Pleuronaia dolabelloides) under the Endangered Species Act of 1973, as amended (Act). These two species are endemic to portions of the Cumberland and Tennessee River systems of Alabama, Kentucky, Mississippi, Tennessee, and Virginia. In total, approximately 2,218 river kilometers (1,380 river miles) in Alabama, Kentucky, Mississippi, Tennessee, and Virginia fall within the boundaries of the critical habitat designation. The effect of this regulation is to designate critical habitat for the fluted kidneyshell and slabside pearlymussel under the Act for the conservation of the species.