HomeFish encyclopediaLampreysLampreysLampreysChestnut lamprey Chestnut lamprey (Ichthyomyzon castaneus) Scientific name: Ichthyomyzon castaneus Girard, 1858 The Chestnut lamprey (Ichthyomyzon castaneus) is a freshwater fish of the family Petromyzontidae. Native range: North America, Hudson Bay, Laurentian Great Lakes and Gulf of Mexico basins. BiologyInhabit lakes and streams. Adults ascend streams to spawn and die soon after egg laying is completed. Ammocoete larvae occur in sand-bottomed and silt-bottomed pools and backwaters. Parasitic. Semelparous.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameIchthyomyzon castaneusFamilyPetromyzontidae (Lampreys)OrderPetromyzontiformes (Lampreys)ClassCephalaspidomorphi (Lampreys)Maximum length38.0Common length20.5EnvironmentFreshwater; demersalClimateSubtropicalDistributionNorth America: Hudson Bay, Laurentian Great Lakes and Gulf of Mexico basins.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceLow, minimum population doubling time 4.5 - 14 years (tm=6) SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026