HomeFish encyclopediaRay-finned fishesSmeltsSlickheadsLongfin smooth-head Longfin smooth-head (Conocara macropterum) Scientific name: Conocara macropterum Vaillant, 1888 The Longfin smooth-head (Conocara macropterum) is a marine fish of the family Alepocephalidae. Native range: Eastern Atlantic, Irish Atlantic slope, Ireland and southern Bay of Biscay to Guinea. Western Atlantic: Bahamas, Gulf of Mexico, and off Brazil. Species factsScientific nameConocara macropterumFamilyAlepocephalidae (Slickheads)OrderOsmeriformes (Smelts)ClassActinopterygii (Ray-finned fishes)Maximum length34.0Depth range800–2200 m (2625–7218 ft)EnvironmentMarine; bathypelagic; depth range 800 - 2200 m, usually 1200 - 1800 mClimateDeep-waterDistributionEastern Atlantic: Irish Atlantic slope, Ireland and southern Bay of Biscay to Guinea. Western Atlantic: Bahamas, Gulf of Mexico, and off Brazil.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceLow, minimum population doubling time 4.5 - 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