The Paraná is the second longest river in South America, flowing almost 4,700km/2,920 miles through Brazil, Paraguay and Argentina. This largest river system in south-central South America has some 300 species of freshwater fishes known.
Stingrays
Nine species of potamotrygonid freshwater river stingrays have been recorded from the Paraná river drainage. This includes the very popular Motoro stingray (Potamotrygon motoro) and the smaller Smooth-back river stingray (P. orbignyi).
Tetras
Tetras form the most diverse component of the freshwater fish fauna of this particular drainage. Comprising species such as this Dawn tetra (Aphyocharax paraguayensis) they account for roughly half the freshwater fishes found here.
Electric fishes
The diversity of electric fishes (gymnotiforms) in the drainage is not as high as in many other South American systems. However, there are still enough species, such as this Glass knifefish (Eigenmannia virescens) for the trade. Pic by Heiko Bleher.
Loricariids
More than 80 species of loricariid have been recorded from the Paraná drainage, but many have not been frequently encountered in the aquarium trade. Those from the Paraná include Pseudohemiodon laticeps, Otocinclus vittatus and Otocinclus vestitus.
Corys
Although the Paraná drainage is not known as the centre of diversity for this group of popular aquarium catfishes, at least 20 species are known from here. Corydoras species found there include the common Peppered cory (Corydoras paleatus).
Catfishes
More than 100 species of catfishes are known in this drainage, making
them the second most diverse group of fishes to be found here. We’ve covered corys and loricariids separately, but the area is also rich in other species, including Hemisorubim platyrhynchos.
Erythrinids
Three species of these voracious ambush predators are known from the Paraná. These are best maintained in a species tank. They can reach to 90cm/35”. Some species can breathe air, are able to survive in water low in oxygen and even move over land between waters. Pic shows Hoplerythrinus unitaeniatus, by Heiko Bleher.
Swamp eels
Just a single species of swamp eel (Synbranchus marmoratus) is known from this drainage. If wanting to keep and maintain this predatory species you will need a tight-fitting tank cover as swamp eels are notable escape artists. Pic by Heiko Bleher.
Killifishes
About 25 species of killifishes from Austrolebias, Leptolebias, Rivulus and Simpsonichthys are known from here. Species, such as this Rivulus punctatus, are common, but killies from the area will seldom be encountered in the trade. Pic by Heiko Bleher.
Cichlids
Cichlids are only moderately diverse in the Paraná drainage and only a little over 25 species are found here. Endemic species frequently encountered in the aquarium trade include the Red-breasted acara, (Laetacara dorsigera, above) and Apistogramma borelli.
Lungfishes
The South American lungfish (Lepidosiren paradoxa) looks similar to the African lungfishes (Protopterus), but is not as commonly encountered. Although predatory, it is relatively docile and can be housed with large tank mates. Pic by Heiko Bleher.
Anostomids
There are three anostomids found in the Paraná drainage. Leporinus friderici friderici, Leporinus obtusidens and the small and attractively patterned Leporellus vittatus. L. frederici frederici is sometimes imported, but the beautiful Leporellus vittatus is sadly rarely seen.
Why not check out our other features in this series:
Where in the world: The Amazon
Where in the world: The Fly river
Where in the world: The River Niger
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