DistributionRead full entry
Range DescriptionThis species is restricted to the Colorado and Concho River drainages in Texas, in the south of the United States (Scott et al. 1989, Smith et al. 1996, Tennant 1998, Werler and Dixon 2000, Ernst and Ernst 2003). The probable historical range is estimated to have included, at a minimum, the Colorado River from Spence Reservoir downstream to the vicinity of Lake Buchanan; Elm, Bluff, and Coyote Creeks (Runnels County); and the entire Concho River (Tom Green and Concho counties) and its headwater tributaries, Dove Creek, Spring Creek, and the South Concho River (Irion and Tom Green counties) (Texas Parks and Wildlife Department). The historical range included about 450 stream km. The current range includes 396 stream km and about 25 km of lake (e.g., lakes Spence, Ivie, and Moonen [=Ballinger Municipal Lake]) (Scott et al. 1989, Smith et al. 1996, Tennant 1998).