Pacific Lamprey and Similar Species
Entosphenus tridentatus
Got a photo? Identify fish instantly with the Fishby app.
Open the appSeveral fish can be confused with Pacific Lamprey. Here are the key differences.
Species often confused with {name}
Western Brook Lamprey
Lampetra richardsoni
Key differences: Smaller size (typically <20 cm), non-parasitic (adults do not feed), and the supraoral lamina has only two cusps (bicuspid) or is sometimes absent. Teeth are blunter and less developed.
River Lamprey
Lampetra ayresii
Key differences: Generally smaller than Pacific Lamprey (up to 30 cm), parasitic but typically on smaller fish, and the supraoral lamina is bicuspid (two cusps), not tricuspid. Teeth are also less robust.
Arctic Lamprey
Lethenteron camtschaticum
Key differences: Found further north, generally smaller, and the supraoral lamina is bicuspid. The teeth arrangement and morphology differ upon close inspection.
Explore Pacific Lamprey
Identify fish anywhere
Free on iOS, Android, and Web. Photo identification, full species details, and more.