Ohio Lamprey

All lampreys have a long, almost eel-like, body with no scales. Lampreys have segments of muscles that are visible along their body called myomeres, and a jawless mouth. In larval lampreys, called ammocoetes, their mouth is not fully developed, very small, and hidden between folds of skin. Adults have a disk shaped mouth with varying amounts of teeth depending on the species. The Ohio lamprey has a single, continuous dorsal fin. Fully grown, Ohio lampreys reach 10–14 inches, but may get to 15 inches.

The Ohio lamprey is found throughout the Ohio River basin in 11 states: Alabama, Georgia, Indiana, Kentucky, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia. The Ohio lamprey used to be found in Illinois, but is now considered to be extirpated; the last sighting was in 1918.

As ammocoetes, Ohio lamprey filter plankton, algae, and other small organic matter. As adults, they attach onto larger prey, such as smallmouth bass, walleyes, redhorse suckers, and trout, feeding on blood and body fluids. Ohio lampreys do not appear to kill the host fish, as they evolved with other fishes in their range. As a result, they do not appear to have a significant effect on populations of their host fishes.