Novel records of stream fishes continue to shape our understanding of species distributions and are often representative of geological and evolutionary histories. We report the discovery of Chrosomus tennesseensis (Tennessee Dace) and confirm previous collections of Etheostoma nigripinne (Blackfin Darter) in the Mobile River Basin. Additionally, we report the rediscovery of Rhinichthys obtusus (Western Blacknose Dace) from the Locust Fork watershed of the Black Warrior River system. The latter species was last collected from the Locust Fork watershed in 1939 and considered extirpated. The discovery of the Tennessee Dace represents the first collection in the Mobile River Basin. These recent collections from the Locust Fork watershed may indicate that a stream-capture event is responsible for the isolation of these populations from the Tennessee River Basin. Subsequent studies should incorporate population-level genetic analyses coupled with historical geological information to understand how these populations became isolated and how recent stream-capture events could inform our understanding of allopatric speciation in aquatic populations.