The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Phractocephalus hemioliopterus
Phractocephalus hemioliopterus
(redtail catfish)

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Phractocephalus hemioliopterus (Bloch and Schneider, 1801)

Common name: redtail catfish

Synonyms and Other Names: Pirarara, cajaro, guacamayo, bigorilo, pez torre, laitu, parabepre.

Taxonomy: available through www.itis.govITIS logo

Identification: A somewhat dated key to pimelodid genera was presented by Schultz (1944). A few distinguishing characteristics and photographs were given by Goulding (1980), Burgess (1989), and Barthem and Goulding (1997).  Distinctive features of the skeleton are detailed in descriptions of extinct fossil species of the genus (Lundberg et al., 2003; Aguilera et al., 2008).  Color photographs, including one of a small juvenile, appeared in Ferraris (1991). The color pattern is quite distinct and photographs of this species are common in aquarium literature. Many references to Phractocephalus hemioliopterus give incorrect spellings of the scientific name (e.g., P. hemiliopterus).

The redtail catfish is distinctively-colored, with a dark grey to black background color, a wide white stripe that extends along the midline (from the mouth to caudal fin) and a red or orange caudal fin.  The dorsal, pelvic, and anal fins are also sometimes red or orange.  It can grow to 1.3 m and 80 kg.  The species is often called the pirarara catfish, especially in literature from South America.

Size: 130 cm and 80 kg.

Native Range: Tropical America. Widespread in Amazon and Orinoco basins of South America (Barthem and Goulding 1997).

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Phractocephalus hemioliopterus are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
AL201620161Mobile Bay
FL198420175Florida Southeast Coast; Peace; South Atlantic-Gulf Region; St. Andrew-St. Joseph Bays; Upper St. Johns
IN201320182Little Calumet-Galien; Lower East Fork White
IA201520151Upper Chariton
MA201420141Nashua River
MN201520151Lower St. Croix
MO200020001Lower Missouri-Moreau
TN201020101Lower Cumberland
TX200420122North Galveston Bay; West Galveston Bay

Table last updated 6/12/2024

† Populations may not be currently present.

Ecology: The redtail catfish is native to the Amazon and Orinoco River basins, where it uses its well-developed chemosensory and tactile abilities to sense prey.  The diet consists primarily of other fishes (primarily characins and catfishes) but also may include fruits, seeds, and crustaceans, especially in seasonally-flooded forests.  It is a habitat generalist, using large rivers, sloughs, streams, lagoons, and estuaries.  It is a slow-moving, bottom-dwelling fish that is thought to attack prey by probing and ambush.  The species is an important component of the Amazonian fishery.  From Goulding (1980), Barthem and Goulding (1997) and Barbarino Duque and Winemiller (2003).

Means of Introduction: Probable aquarium release.

Status: Failed in Florida, Nebraska, Missouri and Texas.  Unknown in Tennessee.  Three individuals collected in proximity to one another.  This species may be able to survive winters in a warm-water refugia.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: This large predacious catfish is somwhat common in the ornamental fish trade. There are no known voucher specimens.

References: (click for full references)

Aguilera, O., J. Bocquentin, J.G. Lundberg & A. Maciente. 2008. A new cajaro catfish (Siluriformes: Pimelodidae: Phractocephalus) from the Late Miocene of Southwestern Amazonia and its relationship to †Phractocephalus nassi of the Urumaco Formation. Paläeontologische Zeitschrift. 82(2):231-245.

Barbarino Duque, A. and K. O. Winemiller.  2003.  Dietary segregation among large catfishes of the Apure and Arauca Rivers, Venezuela. Journal of Fish Biology 63: 410-427.

Barthem, R. and M. Goulding.  1997.  The Catfish Connection:  Ecology, Migration, and Conservation of Amazon Predators.  Columbia University Press, New York.

Burgess, W. E. 1989. An atlas of freshwater and marine catfishes: a preliminary survey of the Siluriformes. Tropical Fish Hobbyist Publications, Inc., Neptune City, NJ.

Courtenay, W. R., Jr., D. P. Jennings, and J. D. Williams. 1991. Appendix 2: exotic fishes. Pages 97-107 in Robins, C. R., R. M. Bailey, C. E. Bond, J. R. Brooker, E. A. Lachner, R. N. Lea, and W. B. Scott. Common and scientific names of fishes from the United States and Canada, 5th edition. American Fisheries Society Special Publication 20. American Fisheries Society, Bethesda, MD.

Ferraris, C. J., Jr. 1991. Catfish in the aquarium. Tetra Press, Morris Plains, NJ.

Goulding, M. 1980. Fishes of the Forest: Explorations in Amazonian Natural History. University of California Press, Los Angeles, CA.

Lundberg J.G. and O. Aguilera. 2003. Additional Specimens and Reinterpretation of the Late Miocene Phractocephalus Catfish (Pimelodidae, Siluriformes) from Urumaco, Venezuela. Neotropical Ichthyology.  1(2):97-109.

Rasmussen, J.L. 1998. Aquatic nuisance species of the Mississippi River basin. 60th Midwest Fish and Wildlife Conference, Aquatic Nuisance Species Symposium, Dec. 7, 1998, Cincinnati, OH.

Schultz, L. P. 1944. The catfishes of Venezuela, with descriptions of thirty-eight new forms. Proceedings of the U.S. National Museum 94(3172):173-338.

FishBase Summary

Author: Pamela J. Schofield, Leo Nico, and Pam Fuller

Revision Date: 6/7/2012

Peer Review Date: 6/7/2012

Citation Information:
Pamela J. Schofield, Leo Nico, and Pam Fuller, 2024, Phractocephalus hemioliopterus (Bloch and Schneider, 1801): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=838, Revision Date: 6/7/2012, Peer Review Date: 6/7/2012, Access Date: 6/12/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/12/2024].

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