Currently found in only two regions in Ontario, the pugnose shiner has an extremely limited distribution and is often absent from potentially suitable habitat within its range. In eastern Ontario, the fish is found only in the upper St. Lawrence River. In southwestern Ontario, it has been found in the Old Ausable Channel, Lake St. Clair and four areas of Lake Erie. However, the fish is already likely extirpated (locally extinct) from two of the Lake Erie sites. The pugnose shiner prefers slow-moving streams and the marshy bays of lakes and ponds. The fish enjoys clear water and plenty of vegetation.

The Pugnose Shiner is a member of the Minnow family and is usually 38 to 51 mm long. The body is fragile, slender, small and somewhat compressed laterally. The Pugnose Shiner has an extremely small, upturned mouth. The eye diameter is relatively large and the snout length slightly smaller than eye diameter. All fins are transparent and the tail is forked. The overall colouration is silvery with pale yellow tints on back and silvery below. Distinct, dark mid-lateral bands extend around the snout, through the eye to the caudal peduncle.