The kelp bass (Paralabrax clathratus), also known as calico bass, is characterized by its similarity to a freshwater largemouth bass. Its third and fourth dorsal spines are of equal length, and are approximately twice the length of the second dorsal spine. The upper part of the head is brownish-olive with random yellow spots, and the upper back is mottled with characteristic white blotches on a brown background. The fins have a yellowish coloration. Breeding males have an orange-colored chin.
There are two rows of the characteristic rectangular white blotches on the back. The bass is easily differentiated from other members of the bass family by these white blotches. Sometimes these bass are confused with yellowtail rockfish or olive rockfish. Rockfish have spines on the operculum (cheek) which are not present on kelp bass.