View source for Biology:Redtail catfish

{{Short description|Species of fish}}
{{Speciesbox
| image = Fish br.jpg
| image_caption =
| fossil_range = {{fossil range|11.6|0|Miocene - Recent}} <ref name=AA/>
| genus = Phractocephalus
| parent_authority = Agassiz, 1829
| species = hemioliopterus
| authority = (Bloch & Schneider, 1801)
| synonyms = {{species list
    |Silurus hemioliopterus |Bloch & Schneider, 1801
    |Pimelodus grunniens |Humboldt, 1821
    |Rhamdia grunniens |Humboldt, 1821
    |Phractocephalus bicolor |Spix & Agassiz, 1829
    }}
}}

The '''redtail catfish''', ''Phractocephalus hemioliopterus'', is a [[Biology:Pimelodidae|pimelodid]] (long-whiskered) [[Biology:Catfish|catfish]]. In Venezuela, it is known as '''cajaro''', in Guyana, it is known as a '''banana catfish''', and in {{wipe|Brazil}}, it is known as '''pirarara''',<ref name=fossil/> stemming from the [[Social:Tupi language|Tupi language]] words ''pirá'' and ''arara''.<ref>{{cite book |last1=Cunha |first1=Antônio Geraldo da |title=Dicionário etimológico da língua portuguesa |date=2010 |publisher=LEXIKON Editora |isbn=9788586368899 |pages=498–499 |edition=4 |url=https://books.google.com/books?id=4yiODwAAQBAJ |accessdate=14 July 2020 |language=Portuguese}}</ref> It is the only extant species of the genus '''''Phractocephalus'''''. This fish is common in the aquarium trade, although its massive adult size makes it unsuitable for all but the largest aquariums.<ref name=sefish/> They feed on fish, crustaceans and fallen fruits.<ref name=diet>{{Cite web|url=https://dwazoo.com/animal/red-tailed-catfish/|title = Red-tailed catfish &#124; the Dallas World Aquarium|date = 25 November 2013}}</ref> They are not evaluated by IUCN.

== Fossil species ==
Although the redtail catfish is the only living representative of this genus, there are other members that date back to the upper Miocene, and are only known from [[Biology:Fossil|fossil]] remains. ''P.&nbsp;nassi'' was described in 2003, from the [[Earth:Urumaco Formation|Urumaco Formation]] at Urumaco, Venezuela. Another fossil species, ''P.&nbsp;acreornatus,'' is known from the Solimões Formation, Acre, {{wipe|Brazil}}.<ref name=AA>[http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=251791 Paleobiology Database]</ref><ref name=fossil>{{cite journal|url=http://www.scielo.br/pdf/ni/v1n2/v1n2a04.pdf|title=The late Miocene ''Phractocephalus'' catfish (Siluriformes: Pimelodidae) from Urumaco, Venezuela: additional specimens and reinterpretation as a distinct species|first=John G.|last=Lundberg|author2=Aguilera, Orangel |journal=Neotropical Ichthyology|volume=1|issue=2|pages=97–109|year=2003|doi=10.1590/S1679-62252003000200004|doi-access=free}}</ref> This genus has a minimum age of about 13.5&nbsp;million years.<ref name=fossil/>

[[File:Redtail catfish - tank - ibaraki - japan - sep 2017.webm|thumb|(video) Redtail catfish swimming in an aquarium]]

==Description==
''Phractocephalus hemioliopterus'' can reach about {{convert|1.8|m|abbr=on}} in length, and about {{convert|80|kg|abbr=on}} in weight.<ref name=record>Fishing. World Records: ''[http://www.fishing-worldrecords.com/scientificname/Phractocephalus%20hemioliopterus/show Phractocephalus hemioliopterus].'' Retrieved 9 May 2013</ref> However, this is exceptionally rare, and most do not approach this size. They average {{convert|42-54|in|ftin m|disp=out}} in length. These colorful large catfishes have a brownish back, with yellow sides, and characteristic orange-red dorsal fin and caudal fin (hence the common name). Sometimes the dorsal, pelvic and anal fins are also red. They have a broad head with long whiskers, dark black body and white underneath that extends from the mouth to the caudal fin. It has a pair of barbels on the upper jaw, and two pairs on the lower jaw. Their whiskers are sensitive and have chemical reception cells which are used as the sense of smell. They breed using external fertilization after laying their eggs. They communicate by making a clicking sound to warn off potential dangers.<ref name=diet/>[[File:Phractocephalus hemioliopterus (Lago Maximo, Brazil, 1 September 1865).jpg|alt=An 1865 watercolor painting of a redtail catfish from Brazil by Jacques Burkhardt.|left|thumb|An 1865 watercolor painting of a Brazilian redtail catfish by Jacques Burkhardt]]

==Distribution and habitat==
The redtail catfish is native to the [[Place:Amazon basin|Amazon]], Orinoco, and Essequibo river basins of South America, in Ecuador, Venezuela, Guyana, Colombia, Peru, Suriname, Bolivia, and {{wipe|Brazil}}.<ref name=fossil/> It is found only in [[Earth:Fresh water|fresh water]], and inhabits larger rivers, streams, and lakes.<ref name=Fishbase>{{FishBase|genus=Phractocephalus|species=hemioliopterus|year=2012|month=February}}</ref><ref name=sefish>[http://www.seriouslyfish.com/species/phractocephalus-hemioliopterus/ Seriously Fish]</ref> They eat during the evening and night and stay motionless during the day. They are bottom-dwellers and move about quite slowly. Red-tailed catfish are territorial fish.<ref name=diet/> Redtail catfish is also an invasive species in Malaysia; they are now found mostly in the Perak River and Pahang River.{{citation needed|date=March 2022}}

==Relationship to humans==
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 {{convert|56|kg|lboz|abbr=on}}.<ref>{{cite web| url=http://wrec.igfa.org/WRecordsList.aspx?lc=AllTackle&cn=Catfish,%20redtail%20%28pirarara%29| date=3 April 2010| title=Catfish, redtail (pirarara)| work=World Record Search| publisher=International Game Fish Association| accessdate=14 July 2014}}</ref>

It is said that the natives do not eat the meat of the redtail catfish because it is black in coloration.<ref name=Axelrod>Axelrod, Herbert R. (1996). ''Exotic Tropical Fishes''. T.F.H. Publications. {{ISBN|0-87666-543-1}}</ref>

In Thailand, it is an alien species that has been introduced by humans, like the common pleco, zebra tilapia, and [[Biology:Alligator gar|alligator gar]].<ref>{{cite web|title=10 ปลาเอเลี่ยนในเมืองไทย ที่กำลังยึดแหล่งน้ำโดยคุณไม่รู้ตัว|url=http://animals.spokedark.tv/?p=2218|archive-url=https://archive.today/20160630043531/http://animals.spokedark.tv/?p=2218|url-status=dead|archive-date=June 30, 2016|publisher=spokedark|date=August 13, 2014|accessdate=June 30, 2016|language=Thai}}</ref>
In some places, it is feared because it has been believed to be the cause of the mysterious drownings of many of the passengers aboard the passenger ship ''Sobral Santos II'' when it sank.

===In the aquarium===
[[File: Phractocephalus hemioliopterus-Dixi.jpg|thumb|''Phractocephalus hemioliopterus'' in an aquarium]]
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'' or pacu, 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,<ref name=Axelrod/> and require tanks of at least {{convert|10000|L|gal|abbr=on}} when fully mature.<ref name=sefish/> Weekly feeding is appropriate for this catfish; overfeeding is a common cause of death in this species.<ref name=planetcatfish>{{cite web|url=http://www.planetcatfish.com/cotm/cotm.php?article_id=77|title=PlanetCatfish::Catfish of the Month::January 2000|publisher=PlanetCatfish.com|date=2006-05-11|accessdate=2007-05-08}}</ref> 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 or [[Biology:Guppy|guppies]]), 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.<ref name=planetcatfish/>

The redtail catfish has been hybridized with other fish, such as the ''[[Biology:Pseudoplatystoma|Pseudoplatystoma]]'' or Tiger Shovelnose Catfish, 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.<ref name=planetcatfish/>

==See also==
*List of freshwater aquarium fish species

==References==
{{Commons|Phractocephalus hemioliopterus}}
<references/>

{{Taxonbar|from=Q1854173}}

{{DEFAULTSORT:Redtail Catfish}}
[[Category:Pimelodidae]]

{{Sourceattribution|Redtail catfish}}