Notropis amplamala, the Longjaw Minnow, is described as a new species for the southern populations of N. buccatus. Notropis amplamala differs from its sister species, N. buccatus, by possessing longer gill rakers (length to width ratio average 2.2, 1.8–2.5 vs. average 1.0, 0.8–1.4), having no breast squamation (vs. breast with scales), and possessing five infraorbital ossicles (vs. four). The two species have a disjunct distribution with N. amplamala occurring in Gulf of Mexico and Atlantic Ocean tributaries from the Pearl River to the Altamaha River, and N. buccatus occurring in Mississippi River, Ohio River, and Atlantic coastal tributaries north of the Cumberland River from eastern Missouri to Virginia and Maryland.