The head is scaleless and the fins lack spines. Suckers are most easily confused with minnows. This is a very diverse family with 50 representatives in Iowa. Most are small, less than 12 inches in length as adults. Native minnows are similar in appearance to suckers, but have fewer than 10 rays in the dorsal fin.
Minnows also have scaleless heads.
Ten species of catfish inhabit Iowa's waters. Catfish have rounded, scaleless bodies with flattened bellies. Strong, sharp spines are located at the insertion of the dorsal and pectoral fins. Catfish are opportunistic in their feeding habits, eating both live and dead animal material. There are 12 representatives of this family found in Iowa.