The spottail shiner originally inhabited the natural lakes, where it is occasional to abundant, and the Mississippi River, where it is rare to occasional. They have been recorded in the Missouri River watershed in Lake Manawa and in Woodbury County. Recently this species was introduced into Rathbun Reservoir.

The spottail shiner is moderately robust and slab-sided. A large, prominent spot at the base of the caudal peduncle, which is the basis of its common name, aids in distinguishing it from other large, pale, and silvery shiners. The color above is very pale olive, and the sides and belly are silvery. A sub-terminal mouth is nearly horizontal and no barbel is present. Flat, hooked pharyngeal teeth are supported on heavy arches and have a variable formula of 0, 4-4, 0 to 2, 4-4, 2. A complete lateral line contains from 36 to 39 scales. The dorsal fin, inserted directly over the pelvic fins, anal fin, and pelvic fins contain 8 rays, while the pectoral fins have from 13 to 15 rays. Dorsal and anal fins are more deeply falcate than other Notropis species.

The spottail shiner is the "big-water" member of the minnow family, reaching its greatest abundance in the natural lakes. It spawns over gravel in creeks or along sandy shores during May and June, but August spawning has been recorded. Adults reach 3 to 4 inches in length. Spottail shiner forage on aquatic insects and larvae, zooplankton, and some plant material.

*Mayhew, J. (editor). 1987. Iowa Fish and Fishing. Iowa Department of Natural Resources, Des Moines, Iowa. 323 pp.