HomeFish encyclopediaRay-finned fishesCatfishEeltail catfishesMaria's tandan Maria's tandan (Oloplotosus mariae) Scientific name: Oloplotosus mariae Weber, 1913 The Maria's tandan (Oloplotosus mariae) is a freshwater fish of the family Plotosidae. Native range: Asia and Oceania, New Guinea. BiologyDorsal spines (total): 1; Dorsal soft rays (total): 5; Anal soft rays: 101 - 116Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameOloplotosus mariaeFamilyPlotosidae (Eeltail catfishes)OrderSiluriformes (Catfish)ClassActinopterygii (Ray-finned fishes)Maximum length15.0EnvironmentFreshwater; demersalClimateTropicalDistributionAsia and Oceania: New Guinea.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceHigh, minimum population doubling time less than 15 months (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