Apteronotidae

family of fishes

Apteronotus is a genus of weakly electric knifefish in the family Apteronotidae, distinguished by the presence of a tiny tail fin. This genus is restricted to tropical and subtropical South America (Amazon, Orinoco, Río de la Plata and Magdalena basins, as well as rivers in western Colombia and the Guianas) and Panama where found in a wide range of freshwater habitats. They feed on small animals.

Sternarchorhynchus is a genus of ghost knifefishes with a long, decurved snout that are found in river basins in tropical South America.

species of fish

Adontosternarchus is a genus of ghost knifefishes found in the Amazon and Orinoco river basins in tropical South America. They have blunt snouts, a dark-spotted or -mottled pattern on a pale background (however, spotting/mottling can be so dense that individuals appear almost all dark) and reach up to in total length. They feed on zooplankton and can be found quite deep, with A. devenanzii recorded down to .

species of fish

species of fish

Magosternarchus is a genus of weakly electric knifefish in the family Apteronotidae, containing two species. They are endemic to Brazil, occurring in large river channels in the Amazon River basin. Both species are unusual benthic predators that specialize in biting off the tails of other knifefishes, and are characterized by their greatly enlarged jaws and teeth. Recent systematic studies indicate that both species should be included in Sternarchella instead of being placed in their own genus.

Megadontognathus is a genus of ghost knifefishes found in river rapids in tropical South America. They are brown with a stubby snout and reach about in total length.

species of fish

Sternarchogiton is a genus of weakly electric knifefish in the family Apteronotidae, all living in the main channel of large rivers in the Amazon and Orinoco basins in South America.

species of fish

Sternarchella, the bulldog knifefishes, is a genus of ghost knifefishes found at depths of in the main channel of large rivers in South America. Most are from the Amazon basin, but S. orthos is found both in the Amazon and Orinoco, S. orinoco is restricted to the Orinoco and S. curvioperculata restricted to the upper Paraná basin (however, the last species likely belongs in another genus, possibly Apteronotus). They are often common in their habitat.

species of fish

Porotergus is a genus of ghost knifefishes found in the Amazon and Essequibo basins in tropical South America. They are found over sandy bottoms in shallow (P. gymnotus) or deep rivers (two remaining). They feed on small aquatic insect larvae. They have a stubby snout and are fairly small knifefish, with the largest species reaching up to in total length.

Compsaraia is a genus of ghost knifefishes found in tropical South America. There are currently three described species in this genus. They are found deep in large rivers in the Amazon and Orinoco basins, and have small eyes and little pigment (appearing whitish in colour).

Platyurosternarchus is a genus of ghost knifefishes found in the Amazon, Orinoco and Essequibo river basins in tropical South America. They are medium-sized knifefish that reach up to in total length and have a relatively long, downwards-pointed tubular snout. They are typically found in streams or near the shore of rivers, often among submerged tree trunks and branches over a leaf-covered bottom where they find their invertebrate prey.