Ohio Lamprey Identification Guide

Key identification features

• Single, continuous dorsal fin rather than two separate fins, a hallmark of its genus
• Moderate size, typically reaching 30-40 cm as an adult
• Wide oral sucker disc lined with strong, clearly radiating rows of teeth used for feeding
• Olive to brown body coloration, unmarked and fairly uniform
• Slender, scaleless, cylindrical body typical of lampreys
• Eyes present and functional in the transformed adult stage

Common look-alikes

• Silver lamprey shares the same undivided dorsal fin but its lateral teeth are mostly single-pointed rather than the Ohio Lamprey's paired, bicuspid teeth.
• Least brook lamprey is much smaller and non-parasitic, with a noticeably weaker, reduced set of oral teeth.
• Sea lamprey is far larger with a mottled body pattern and lives mostly in different, more northeastern drainages.

Where you'll see one

Ohio Lampreys inhabit freshwater rivers and streams of the Ohio, Tennessee, and Cumberland drainages within the wider Mississippi River basin across the eastern-central United States, where adults attach to host fish over gravel riffles and clean-flowing runs.