Rock bass can be easily distinguished from shadow bass by the well-defined rows of dark spots along the sides, particularly below the lateral line, which usually contains 37 to 46 scales. The dorsal fin has 10 to 13 spines and 10 to 12 rays. The anal fin has five to seven spines and nine to 11 rays. The mouth is large, and the upper jaw extends to below the middle of the eye. The back and sides of this species are olive to light brown with distinct horizontal rows of black spots. The vertical fins have a light yellowish background. The basal areas are mottled with brown or gray, and the distal portion has two to four dark bands. The anal fin on adult males has a distinct black margin. The iris is red to reddish orange. Venter color can vary from white to light brown or charcoal. Adult size: 8 to 10 inches.