Giant short-tailed river stingray (Potamotrygon brachyura)

General data

Main name: Giant short-tailed river stingray
Climates: Tropical
Habitat: Freshwater
Native: South America
Distribution: Parana, Rio de la Plata, Uruguay River

Classification

Genus: Potamotrygon - Potamotrygon
Family: Potamotrygonidae - Southamerican freshwater stingrays
Order: Myliobatiformes - Stingrays
Class: Elasmobranchii - Sharks and Rays
Superclass: Chondrichthyes - Cartilaginous fishes

Description

The short-tailed river stingray (Potamotrygon brachyura) is a species of river stingray (family Potamotrygonidae) native to the Río de la Plata Basin in South America. It is sometimes known as the giant freshwater stingray, but this name is typically used for the southeast Asian Himantura polylepis. Growing to a disc diameter of about 1.5 m (5 ft) and a weight of 220 kg (490 lb), the short-tailed river stingray is the largest freshwater species in its famil and one of the heaviest strict freshwater fish in South America, only matched by the arapaima (Arapaima) and piraíba catfish (Brachyplatystoma filamentosum). The primary threat to the short-tailed river stingray is fishing for food and as a game fish, but it is also under pressure from habitat loss and occasionally caught for aquaria. They have a dark pattern on their backs, probably used as camouflage. The ray’s tail is very muscular and thick, covered with short spines at the base and a venomous sting at the end. Distribution The short-tailed river stingray is found in the Río de la Plata Basin, including the Paraguay, Paraná and Uruguay Rivers in the countries of Argentina, Brazil, Paraguay and Uruguay. It may also range into Bolivia in the Pilcomayo River (a tributary of the Paraguay River), but this remains unconfirmed. In the north it ranges from the upper Paraguay River basin, including the Pantanal, and south to the lowermost freshwater sections of the Río de la Plata. Unlike some other freshwater rays, it has not been able to spread to the upper Paraná River basin after the Itaipu Dam flooded the Guaíra Falls, which represented a natural barrier to its range.

Taxonomy of Fishes

Osteichthyes - Bony fishes->
Chondrichthyes - Cartilaginous fishes->
- Elasmobranchii - Sharks and Rays->
  - Lamniformes - Mackerel sharks->
  - Carcharhiniformes - Ground sharks->
  - Rhinopristiformes - Shovelnose rays->
  - Torpediniformes - Electric rays->
  - Rajiformes - Skates and rays->
  - Orectolobiformes - Carpet shark->
  - Squatiniformes - Angelsharks->
  - Heterodontiformes - Bullhead and horn sharks->
  - Hexanchiformes - Six-gill sharks->
  - Myliobatiformes - Stingrays->
    
    Dasyatidae - Stingrays->
    
    Mobulidae - Manta rays->
    
    Potamotrygonidae - Southamerican freshwater stingrays->
    
    Potamotrygon - Potamotrygon->
    
    Ocellate river stingray (Potamotrygon motoro)
    
    Tiger river stingray (Potamotrygon tigrina)
    
    Giant short-tailed river stingray (Potamotrygon brachyura)
    
    Amanda’s River Stingray (Potamotrygon amandae)
    
    Xingu River ray (Potamotrygon leopoldi)
    
    Potamotrygon adamastor (Potamotrygon adamastor)
    
    Potamotrygon albimaculata (Potamotrygon albimaculata)
    
    Potamotrygon amazona (Potamotrygon amazona)
    
    Potamotrygon boesemani (Potamotrygon boesemani)
    
    Thorny river stingray (Potamotrygon constellata)
    
    Largespot river stingray (Potamotrygon falkneri)
    
    Potamotrygon garmani (Potamotrygon garmani)
    
    Bigtooth river stingray (Potamotrygon henlei)
    
    Porcupine river stingray (Potamotrygon histrix)
    
    Potamotrygon humerosa (Potamotrygon humerosa)
    
    Potamotrygon jabuti (Potamotrygon jabuti)
    
    Potamotrygon limai (Potamotrygon limai)
    
    Magdalena river stingray (Potamotrygon magdalenae)
    
    Potamotrygon marinae (Potamotrygon marinae)
    
    Red-blotched river stingray (Potamotrygon ocellata)
    
    Smooth back river stingray (Potamotrygon orbignyi)
    
    Potamotrygon pantanensis (Potamotrygon pantanensis)
    
    Great freshwater stingray (Potamotrygon rex)
    
    Rosette river stingray (Potamotrygon schroederi)
    
    Potamotrygon schuhmacheri (Potamotrygon schuhmacheri)
    
    Raspy river stingray (Potamotrygon scobina)
    
    Parnaiba river stingray (Potamotrygon signata)
    
    Potamotrygon tatianae (Potamotrygon tatianae)
    
    Potamotrygon wallacei (Potamotrygon wallacei)
    
    Maracaibo river stingray (Potamotrygon yepezi)
    
    Plesiotrygon - Antenna rays->
    
    Heliotrygon - Heliotrygon->
    
    Paratrygon - Paratrygon->
    
    Styracura - Styracura->
    
    Gymnuridae - Butterfly rays->
    
    Myliobatidae - Eagle ray->
    
    Urotrygonidae - American round stingrays->
    
    Aetobatidae - Pacific eagle rays->
    
    Hexatrygonidae - Sixgill stingrays->
    
    Plesiobatidae - Deepwater stingrays->
    
    Rhinopteridae - Cownose rays->
    
    Urolophidae - Round rays->
    
    Zanobatidae - Panrays->
  - Squaliformes - Sleeper and dogfish sharks->
  - Echinorhiniformes - Bramble sharks->
  - Pristiophoriformes - Saw sharks->
- Holocephali - Chimaeras->
Agnatha - Jawless fishes->