Recent genetic analysis has shown that Longear Sunfish should be split into several different species. Perhaps the most striking of these new species is the westernmost: The Rio Grande Longear Sunfish. The Rio Grande Longear Sunfish is found in Texas, Mexico, New Mexico, and extends into Oklahoma, Kansas, Louisiana, Arkansas, and Missouri. They can be distinguished from typical Longear Sunfish by their shorter pectoral fin length, level opercular flap angle, longer dorsal and anal fin spines, longer upper and lower jaws, deeper caudal peduncle, and smaller opercular flap.