Downstream Intrabasin Range Extension for the Endangered Plicate Rocksnail, Leptoxis plicata (Conrad) (Gastropoda: Pleuroceridae)

Two new locations were documented for Leptoxis plicata (Plicate Rocksnail), listed as endangered by the US Fish and Wildlife Service in 1998. Plicate Rocksnail is endemic to the Black Warrior River system in Alabama and was thought to be restricted to 15 shoals in a 30-km reach of Locust Fork, all upstream of the US Highway 78 crossing. During a routine biological survey, Plicate Rocksnail was found at two additional shoals downstream of the Highway 78 crossing: one 3.5 km (87°01′00″W, 33°41′30″N) and the other 5.2 km (87°00′30″W, 33°39′20″N) downstream. The rocksnails were extremely abundant at each of these locations and varied in size from small, apparently young of the year, to large adults. These two new locations extend the intrabasin range of this species over 5 km farther downstream than previously reported.