This article is about the South American redtail catfish. For the Asian redtail catfish, see Hemibagrus wyckioides.

The redtail catfish, Phractocephalus hemioliopterus, is a pimelodid (long-whiskered) catfish named for its orange-red caudal fin. In Venezuela it is known as cajaro and in Brazil it is known as pirarara.^[1] It is the only extant species of the genus Phractocephalus. This fish originates from South America in the Amazon, Orinoco, and Essequibo river basins. Despite reaching 1.8 m (5 ft 11 in) in length and 80 kg (180 lb) in weight,^[2] this fish is a common aquarium fish.

Extinct Phractocephalus [edit]

Although the redtail catfish is the only living representative of this genus, there are other members that date back to the upper Miocene. P. nassi was described in 2003, and is from Urumaco, Venezuela. Another undescribed member is known to exist from Acre, Brazil.^[1] This genus has a minimum age of about 13.5 million years.^[1]

Distribution and habitat [edit]

The redtail catfish is native to the Amazon, Orinoco, and Essequibo river basins of South America.^[1] It is found only in fresh water.^[3]

Relationship to humans [edit]

Due to the potential large size of this species, redtail catfish are considered a game fish by anglers. The current (IGFA) world record for weight belongs to the Brazilian Gilberto Fernandes with 56 kg (123 lb 7 oz) date=03-Apr-2010 http://wrec.igfa.org/WRecordsList

It is said that the natives do not eat the meat of the Redtail catfish because it is black in coloration.^[4] However, the redtail catfish has been hybridized with other fish such as the Tiger Shovelnose Pseudoplatystoma sp. Through the use of hormones in attempts to create a viable food fish, the Tiger redtail catfish; these hybrid fish sometimes make it into the aquarium hobby under a variety of common names.^[5]

In the aquarium [edit]

The redtail catfish is an extremely popular fish in Amazonian themed exhibits at public aquaria, where they are often housed with other large fish such as Colossoma macropomum, Arapaima gigas, and other large catfish.

Juveniles are often available as aquarium fish despite their eventual large size. In an aquarium where they may be well-fed, these fish can grow quite rapidly.^[4] Weekly feeding is appropriate for this catfish; overfeeding is a common cause of death in this species.^[5] It feeds heavily on live and dead fishes and other meat. Even as a juvenile of only a few inches in length, they are able to swallow many of the more common aquarium fish such as tetras, and it is only appropriate to house this fish with other species of relatively large size. Redtail catfish also have a habit of swallowing inedible objects in the aquarium. Though these are often regurgitated, both the swallowing and the regurgitation can present a problem for the fish, and these objects are best kept out of the aquarium.^[5] It is important that these fish are housed in large aquariums. A minimum size tank for a full grown (4-5 feet) is 1000+ gallons.

See also [edit]

• List of freshwater aquarium fish species

References [edit]

Wikimedia Commons has media related to: Phractocephalus hemioliopterus

1. ^ ^{a b c d} Lundberg, John G.; Aguilera, Orangel (2003). "The late Miocene Phractocephalus catfish (Siluriformes: Pimelodidae) from Urumaco, Venezuela: additional specimens and reinterpretation as a distinct species" (PDF). Neotropical Ichthyology 1 (2): 97–109. doi:10.1590/S1679-62252003000200004. 
2. ^ Fishing World Records: Phractocephalus hemioliopterus. Retrieved 9 May 2013
3. ^ Froese, Rainer and Pauly, Daniel, eds. (2012). "Phractocephalus hemioliopterus" in FishBase. February 2012 version.
4. ^ ^{a b} Axelrod, Herbert R. (1996). Exotic Tropical Fishes. T.F.H. Publications. ISBN 0-87666-543-1
5. ^ ^{a b c} "PlanetCatfish::Catfish of the Month::January 2000". PlanetCatfish.com. 2006-05-11. Retrieved 2007-05-08.