HomeFish encyclopediaRay-finned fishesSpiny eelsSwamp-eelsAustralian swamp eel Australian swamp eel (Ophisternon gutturale) Scientific name: Ophisternon gutturale Richardson, 1845 The Australian swamp eel (Ophisternon gutturale) is a freshwater fish of the family Synbranchidae. Native range: Oceania, Papua New Guinea and northern Australia. BiologyOccur in backwaters of rivers, swamps, and stagnant ponds. Inhabit soft bottom sediments in quiet, well-vegetated backwaters of brackish estuaries and nearby swamps. Found in lower freshwater reaches of rivers. Cryptic, nocturnally active species, which burrow in bottom sediments. The male guards and builds nest or burrow. The best chance of sighting this elusive fish is by spotlighting along thickly vegetated margins of suitable habitats at night. They are capable of surviving short periods out of water. A current taxonomic study of this family indicates this species probably should be placed in a new genus.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameOphisternon gutturaleFamilySynbranchidae (Swamp-eels)OrderSynbranchiformes (Spiny eels)ClassActinopterygii (Ray-finned fishes)Maximum length60.0Common length20.0EnvironmentFreshwater; brackish; demersalClimateTropicalDistributionOceania: Papua New Guinea and northern Australia.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceMedium, minimum population doubling time 1.4 - 4.4 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