American Brook Lamprey and Similar Species
Lethenteron appendix
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Open the appSeveral fish can be confused with American Brook Lamprey. Here are the key differences.
Species often confused with {name}
Sea Lamprey
Petromyzon marinus
Key differences: The Sea Lamprey is parasitic, much larger (up to 120 cm), and has a large oral disc with numerous sharp, recurved teeth. It also has a more distinct separation between its two dorsal fins and a more mottled coloration.
Northern Brook Lamprey (European)
Lethenteron planeri
Key differences: Historically, L. appendix was considered a subspecies or synonym of L. planeri. Genetic studies have largely supported their distinction as separate species. Morphologically, they are very similar, but L. appendix generally has a slightly larger oral disc and a more robust body. Geographic range is the primary differentiator.
Chestnut Lamprey
Ichthyomyzon castaneus
Key differences: The Chestnut Lamprey is parasitic and has a more developed oral disc with sharper teeth. It also typically has a single, continuous dorsal fin or two very closely spaced fins, unlike the distinctly separated or barely touching dorsals of L. appendix.
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