Short-tailed river stingray | |
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Juvenile | |
Conservation status | |
Data Deficient (IUCN 3.1) | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Chondrichthyes |
Subclass: | Elasmobranchii |
Order: | Myliobatiformes |
Family: | Potamotrygonidae |
Genus: | Potamotrygon |
Species: | P. brachyura |
Binomial name | |
Potamotrygon brachyura (Günther, 1880) |
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 Urogymnus polylepis.
Growing to a disc diameter of about 1.9 m (6.2 ft) and a weight of 220 kg (490 lb), with unconfirmed records of even larger specimens, the short-tailed river stingray is the largest freshwater species in its family 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 (if not released), but it is also under pressure from habitat loss and occasionally caught for aquaria.
Description
The short-tailed river stingray is circular in shape and humped in the back. The species can reach about 1.9 m (6 ft) in disc diameter and 220 kg (490 lb) in weight, making it the largest freshwater species in the family Potamotrygonidae. 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.
Lifestyle
Female short-tailed river stingrays give birth to up to 19 fully formed young stingrays per litter. The pups start off eating plankton and then move on to consume small mollusks, crustaceans, the larvae of aquatic insects, and fish.
References
- ^ Charvet-Almeida, P.; Soto, J.M.R.; Pinto de Almeida, M. (2009). "Potamotrygon brachyura". IUCN Red List of Threatened Species. 2009: e.T161687A5480430. doi:10.2305/IUCN.UK.2009-2.RLTS.T161687A5480430.en. Retrieved 20 November 2021.
- ^ Froese, Rainer; Pauly, Daniel (eds.). "Potamotrygon brachyura". FishBase. January 2017 version.
- ^ Oddone, M.C., G. Velasco & G. Rincon (2008). Occurrence of freshwater stingrays (Chondrichthyes: Potamotrygonidae) in the Uruguay River and its tributaries, Uruguay, South America. International Journal of Ichthyology 14 (2): 69-76.
- ^ Fishing World Records: Potamotrygon brachyura. Retrieved 3 August 2023.
- ^ Lucifora; Barbini; Vegh; et al. (2016). "Geographic distribution of the short-tailed river stingray (Potamotrygon brachyura): assessing habitat loss and fishing as threats to the world's largest obligate freshwater elasmobranch" (PDF). Marine and Freshwater Research. 67 (10): 1463–1478. doi:10.1071/MF15003. hdl:11336/38346. S2CID 52245299. Archived from the original (PDF) on 2019-02-19.
- ^ "Short-tailed river stingray". Discovery. Archived from the original on 7 January 2013.
- ^ River Monsters, First Edition, Da Capo Press, 2011, p. 165
- Last; White; de Carvalho; Séret; Stehmann; Naylor, eds. (2016). Rays of the World. CSIRO. pp. 626 & 630. ISBN 9780643109148.
- River Monsters, First Edition, Da Capo Press, 2011, p. 162
External links
Taxon identifiers | |
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Potamotrygon brachyura |