The chestnut lamprey is even more rarely taken than the silver lamprey. It has been reported in the Mississippi River throughout Iowa by the Upper Mississippi River Conservation Committee, but from no other location in the state. The chestnut lamprey differs in appearance from the silver lamprey by several features. The dorsal fin is continuous without the double lobes. The mouth is a sucking disc, but the circumoral teeth are nearly all bicuspid, or two pointed. There are 51 to 54, usually more than 52, myomeres or segments in the body between the last gill slit and the anus. This lamprey attains lengths of 8 to 13 inches.

The life history of the chestnut lamprey is very similar to that of the silver lamprey. It usually ascends small streams to spawn in the spring of the year. Larvae require several years to reach the adult stage, at which time it returns to the larger streams and remains there until spawning the following spring. The parasitic stage of life continues for one year. Adult chestnut lamprey are parasitic and live largely by attaching themselves to fishes. The digestive tract is well developed. These animals are never taken by hook-and-line; hence they are of no importance to the anglers, except possibly as bait for other fish.

*Mayhew, J. (editor). 1987. Iowa Fish and Fishing. Iowa Department of Natural Resources, Des Moines, Iowa. 323 pp.