Identification: Weber (1991, 1992) assigned sailfin catfishes to three genera and used the name Liposarcus pardalis for this species. Armbruster (1997), after a detailed systematic review, placed the genus Liposarcus into the synonymy of Pterygoplichthys. Weber (1992) provided a key and distinguishing characteristics and photographs of specimens; Armbruster and Page (2006) present a revised key to species in the genus Pterygoplichthys (except P. ambrosettii). Pterygoplichthys and other suckermouth armored catfishes (family Loricariidae) can be distinguished from native North American catfishes (Ictaluridae) by the presence of flexible bony plates (absent in ictalurids) and a ventral suctorial mouth (terminal in ictalurids). Pterygoplichthys is often confused with Hypostomus: these genera can be distinguished by the number of dorsal fin rays (7-8 in Hypostomus vs. 9-14 in Pterygoplichthys).
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 Pterygoplichthys pardalis are found here.
Table last updated 3/31/2025
† Populations may not be currently present.
Impact of Introduction: Male members of the genus Pterygoplichtys dig out river banks to create burrows in which an attracted female will lay and guard her eggs. In large numbers, this burrowing behavior by Pterygoplichthys contributes to problems with siltation. In addition, the burrows potentially destabilize the banks, leading to an increased rate of erosion (Nico et al. 2009). Diurnal aggregations of Pterygoplichthys can potentially alter nutrient dynamics by creating biogeochemical hotspots through nitrogen and phosphorus excretion and remineralization (Capps and Flecker 2013). Because it grazes and removes attached algae, and also feeds on benthic organisms and detritous, this introduced catfish may be having a significant impact on the aquatic food base and, therefore, negatively effecting native invertebrate and vertebrate species (Nico, personal observations).
Pterygoplichthys paradalis was the most important dietary item for Common Snook (Centropomus undecimalis) in southeastern Mexico, where they were also consumed by Tarpon (Megalops atlanticus), Cormorants (Phalacrocorax brasilianus), and Osprey (Pandion haliaetus) (Toro-Ramírez 2014).
References: (click for full references)
Armbruster, J.W., and L.M. Page. 2006. Redescription of
Pterygoplichthys punctatus and description of a new species of
Pterygoplichthys (Siluriformes: Loricariidae). Neotropical Ichthyology 4(4):401-409.
http://dx.doi.org/10.1590/S1679-62252006000400003.
Capps, K.A., and A.S. Flecker. 2013. Invasive fishes generate biogeochemical hotspots in a nutrient-limited system. PLoS ONE 8(1):e54093. http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054093.
Capps, K.A., L.G. Nico, M. Mendoza-Carranza, W. Arévlo-Frías, A.J. Ropicki, S.A. Heilpern, and R. Rodiles-Hernández. 2011. Salinity tolerance of non-native suckermouth armoured catfish (Loricariidae: Pterygoplichthys) in south-eastern Mexico: implications for invasion and dispersal. Aquatic Conservtion: Marine and Freshwater Ecosystems 21:528-540.
Nico, L.G., H.L. Jelks, and T. Tuten. 2009. Non-native suckermouth armored catfishes in Florida: description of nest burrows and burrow colonies with assessment of shoreline conditions. Aquatic Nuisance Species Research Program Bulletin 9(1): 1-30.
Toro-Ramírez, A., A.T. Wakida-Kusunoki, L.E. Amador-del Ángel, and J.L. Cruz-Sánchez. 2014. Common snook [Centropomus undecimalis (Bloch, 1792)] preys on the invasive Amazon sailfin catfish [Pterygoplichthys pardalis (Castelnau, 1855)] in the Palizada River, Campeche, southeastern Mexico. Journal of Applied Ichthyology 30:532-534. https://onlinelibrary.wiley.com/doi/full/10.1111/jai.12391.
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.