The swallowtail shiner, Notropis procne, is a North American species of freshwater fish in the Cyprinidae family. It has a slender and long body of about 40–55 mm. The shiner has a pale yellow back with a blue stripe on its silver side. It also has a silvery white belly. Its fins are yellowish and it has a dorsal fin originating above the back half of the pelvic fin base and a tail fin with a black spot at its base. Its snout is either slightly pointed or slightly rounded. The swallowtail shiner lives in warm creeks and in river pools. It is known to live in Virginia in the New River system and near the Atlantic slope. It is often found near plants. The shiner eats insects, worms, mites, microcrustaceans, and algae. Juvenile shiners mature after a year and spawn from mid-May to July when the water reaches a temperature of 25.6°C. Fecundity is unknown in this species and it breeds well in aquariums. It is similar to the closely related Cape Fear shiner and sand shiner.