HomeFish encyclopediaRay-finned fishesCarpsMinnows or carpsHardhead Hardhead (Mylopharodon conocephalus) Scientific name: Mylopharodon conocephalus Baird & Girard, 1854 The Hardhead (Mylopharodon conocephalus) is a freshwater fish of the family Cyprinidae. Native range: North America, Sacramento-San Joaquin and Russian River drainages in California, USA. BiologyInhabits deep, rocky and sandy pools of small to large rivers.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameMylopharodon conocephalusFamilyCyprinidae (Minnows or carps)OrderCypriniformes (Carps)ClassActinopterygii (Ray-finned fishes)Maximum length100.0Common length35.0EnvironmentFreshwater; demersalClimateSubtropicalDistributionNorth America: Sacramento-San Joaquin and Russian River drainages in California, USA.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceVery Low, minimum population doubling time more than 14 years (Preliminary K or Fecundity.) SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026