HomeFish encyclopediaRay-finned fishesCharacinsPencilfishesLeast pencilfish Least pencilfish (Nannostomus minimus) Scientific name: Nannostomus minimus Eigenmann, 1909 The Least pencilfish (Nannostomus minimus) is a freshwater fish of the family Lebiasinidae. Native range: South America, Potaro and Mazaruni River basins in Guyana. Species factsScientific nameNannostomus minimusFamilyLebiasinidae (Pencilfishes)OrderCharaciformes (Characins)ClassActinopterygii (Ray-finned fishes)Maximum length2.3EnvironmentFreshwater; benthopelagicClimateTropicalDistributionSouth America: Potaro and Mazaruni River basins in Guyana.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessUsesFisheries: of no interest SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026