River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family Potamotrygonidae in the order Myliobatiformes, one of the four orders of batoids, cartilaginous fishes related to sharks. They are found in rivers in tropical and subtropical South America. A single marine genus, Styracura, of the tropical West Atlantic and East Pacific are also part of Potamotrygonidae. They are generally brownish, greyish or black, often with a mottled, speckled or spotted pattern, have disc widths ranging from 31 to 200 centimetres (1.0–6.6 ft) and venomous tail stingers. River stingrays feed on a wide range of smaller animals and the females give birth to live young. There are more than 35 species in five genera.
The European river lamprey, also known as the river lamprey or lampern, is a species of freshwater lamprey.
The giant freshwater stingray is a species of stingray in the family Dasyatidae. It is found in large rivers and estuaries in Southeast Asia and Borneo, though historically it may have been more widely distributed in South and Southeast Asia. The widest freshwater fish and the largest stingray in the world, this species grows up to 2.2 m (7.2 ft) across and can exceed 300 kg (660 lb) in weight. It has a relatively thin, oval pectoral fin disc that is widest anteriorly, and a sharply pointed snout with a protruding tip. Its tail is thin and whip-like, and lacks fin folds. This species is uniformly grayish brown above and white below; the underside of the pectoral and pelvic fins bear distinctive wide, dark bands on their posterior margins.
Anabarilius polylepis s a species of freshwater ray-finned fish belonging to the family Xenocyprididae, the East Asian minnows or sharpbellies. This species is endemic to Yunnan, China. It only occurs in Dian Lake and Songhuaba reservoir in Kunming. It was once a major commercial fish species, but it has not been confirmed in the lake since the 1970s. Its decline is attributed to many factors: introduced fish species, decreasing water quality, the loss of macrophytes, over-fishing, and the loss of breeding sites due to siltation and blocked access.
Anaecypris hispanica, the Spanish minnowcarp, is a small species of ray-finned fish species in the family Cyprinidae. It is endemic to the Iberian Peninsula and is found in the basin of the Guadiana River in southern Spain and Portugal. Its natural habitats are rivers and intermittent rivers which are shallow, highly oxygenated, have a water temperature of no more than 25 °C (77 °F) and have a coarse stream bed. It is threatened by habitat loss. They grow to a maximum size of 60 mm (2.4 in) and live for three years.
Barbus haasi, or the Catalonian barbel or redtail barb Catalan: barb cua-roig; Spanish: barbo colirrojo or barbo de cola roja), is a species of freshwater fish in the family Cyprinidae.
The Andalusian barbel, also called gypsy barbel, is a freshwater fish species in the family Cyprinidae. It is here placed in Luciobarbus following the IUCN, but that genus is very closely related to the other typical barbels and perhaps better considered a mere subgenus of Barbus. The Andalusian barbel was formerly included in L. bocagei as a subspecies.
The Northern straight-mouth nase is a species of ray-finned fish in the family Cyprinidae. It is found in Portugal and Spain. Its natural habitat is rivers. It is threatened by habitat loss.
Parachondrostoma turiense is a species of ray-finned fish in the family Cyprinidae. It is found only in Spain. Its natural habitat is rivers. It is threatened by habitat loss.
The Southern straight-mouth nase, Pseudochondrostoma willkommii, is a species of cyprinid fish, which is found in Portugal and Spain. Its natural habitats are rivers and water storage areas, and it is threatened by habitat loss.
Squalius carolitertii, the Northern Iberian chub, is a species of fresh-water fish in the family Cyprinidae. It is found in Portugal and Spain, and known there as the bordallo, escalo or gallego.
Telestes polylepis is a species of ray-finned fish in the family Cyprinidae. It is found only in a 4 km2 (1.5 sq mi) area of karst landscape in Ogulinsko polje, northwestern Croatia.
Himantura fluviatilis, the Ganges whip ray, is an obscure species of stingray in the family Dasyatidae, apparently endemic to the Ganges River system and adjacent marine waters. With an oval pectoral fin disc and long projecting snout, it closely resembles, and may be the same species as Himantura chaophraya. Growing to 1.4 m (4.6 ft) across, it is a plain dark colour above, and lighter below with wide dark bands on the lateral disc margins. The International Union for Conservation of Nature (IUCN) has listed this species as Endangered, as it faces overfishing and habitat degradation within its heavily populated range.
The smallscale yellowfish is a South African species of freshwater fish in the cyprinid family. It is native to the Limpopo, Incomati and Pongolo drainages.
Achondrostoma arcasii, termed the bermejuela, is a species of freshwater fish in the family Cyprinidae. It is found in the Douro River in northern Portugal and in rivers draining to both the Atlantic Ocean and the Mediterranean, including the Ebro River, in northern Spain where it is threatened by loss of habitat caused by the building of canals and the construction of dams, as well as by introduced predators and water pollution.
The short-tailed river stingray is a species of river stingray 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.
Pseudochondrostoma is a genus of cyprinid fish that occurs in the Iberian Peninsula. They are commonly known as the straight-mouth nases.
Iberian gudgeon is a species of gudgeon, a small freshwater in the family Cyprinidae. It is widespread only in the Iberian Peninsula where it is indigenous in the Ebro and Bidasoa drainage, and in France in the Adour drainage, as well as Andorra. It has been introduced throughout the Iberian Peninsula, including Portugal, It is a freshwater demersal fish, up to 11.9 cm long.
Unio tumidiformis is a species of bivalve belonging to the family Unionidae. It is endemic to the southwestern Iberian Peninsula. Existing populations are known from the Guadiana, Mira, and Sado Rivers in Portugal and Spain.
Iguanodectes polylepis is a species of freshwater fish from the rivers of South America. Its range is restricted to Brazil, where it inhabits the Madeira and Purus river basins. It is one of the larger members of the genus, but remains generally small, only a little over a quarter-foot long.
