The Guadalupe bass is a member of the Centrarchidae family and is similar to the spotted bass (see: Bass, Spotted) in appearance. It has 10 to 12 dark bars along its sides, which are less distinct in older fish; it usually has 16 pectoral rays and 26 to 27 scales around the caudal peduncle.
It can grow to almost 16 inches and usually weighs less than a pound. The all-tackle world record is a 3-pound, 11-ounce Texas fish taken in 1983. In North America, Guadalupe bass are restricted to the Edwards Plateau in the Brazos, Colorado, Guadalupe, San Antonio, and upper Nueces (where introduced) River drainages in southern Texas. They occur in gravel riffles, runs, and flowing pools of creeks, as well as in small to medium rivers.