Loricariidae

Loricariidae is the largest family of catfish, with over 90 genera and just over 680 species. Loricariids originate from freshwater habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are noted for the bony plates covering their bodies and their suckermouths. Several genera are sold as "plecos", notably the suckermouth catfish, Hypostomus plecostomus, and are popular as aquarium fish.

Common names

Members of the family Loricariidae are commonly referred to as loricariids, suckermouth catfishes, armoured catfish, or suckermouth armoured catfish. The name "plecostomus", and its shortened forms "pleco" and "plec", are used for many Loricariidae, since Plecostomus plecostomus was one of the first loricariid species imported for the fish-keeping hobby.
Some loricariids are not normally considered "plecostomus", such as Farlowella catfish.
In their native range, these fish are known as cascudos or acarís.

L-numbers

Some types of loricariids are often referred to by their 'L-number'; this has become common since imports of loricariid catfish from South America often included specimens that had not been taxonomically described. Currently, L-numbers are used not only by fish-keeping enthusiasts, but also by biologists, since they represent a useful stopgap until a new species of fish is given a full taxonomic name. In some cases, two different L-numbered catfish have turned out to be different populations of the same species, while in other cases, multiple species have all been traded under a single L-number.

Taxonomy and evolution

Because of their highly specialized morphology, loricariids have been recognized as a monophyletic assemblage in even the earliest classifications of the Siluriformes, meaning they consist of a natural grouping with a common ancestor and all of its descendants. Loricariidae is one of seven families in the superfamily Loricarioidea, along with Amphiliidae, Trichomycteridae, Nematogenyidae, Callichthyidae, Scoloplacidae, and Astroblepidae. Some of these families also exhibit suckermouths or armor, although never in the same individual, as in loricariids.
This is the largest catfish family, including about 684 species in around 92 genera, with new species being described each year. However, this family is in flux, and revisions are likely. For example, the subfamily Ancistrinae is accepted as late as the 2006 edition of Nelson's Fishes of the World; it later becomes grouped as a tribe, because of its recognition as a sister group to the Pterygoplichthyini. Under Ambruster, six subfamilies are recognized: Delturinae, Hypoptopomatinae, Hypostominae, Lithogeneinae, Loricariinae, and Neoplecostominae.
Monophyly for the family is strongly supported, except, possibly, the inclusion of Lithogenes. Lithogenes is the only genus within the subfamily Lithogeneinae. This genus and subfamily, the most basal group in Loricariidae, is the sister group to the rest of the family. Neoplecostominae are the most basal group among the loricariids with the exception of Lithogeneinae. However, the genera of Neoplecostominae do not appear to form a monophyletic assemblage. The two subfamilies Loricariinae and Hypoptopomatinae appear to be generally regarded as monophyletic. However, the monophyly and composition of the other subfamilies are currently being examined and will likely be altered substantially in the future. The Hypostominae are the largest subfamily of Loricariidae. It is made up of five tribes. Four of the five tribes, Corymbophanini, Hypostomini, Pterygoplichthyini, and Rhinelepini, include about 24 genera. The fifth and largest tribe, Ancistrini, includes 30 genera.
Loricariid fossils are extremely rare. The earliest known definitive taxon is Taubateia from the Late Oligocene-Early Miocene in Brazil. The putative Cenomanian member Afrocascudo, initially described as the earliest loricariid catfish in 2024, might represent a juvenile obaichthyid lepisosteiform, possibly a junior synonym of Obaichthys, though this has been disputed based on the complete ossification of the bones indicating full maturity and the absence of important holostean characters. Within the superfamily Loricarioidea, the Loricariidae are the most derived; in this superfamily, the trend is toward increasingly complex jaw morphology, which may have allowed for the great diversification of the Loricariidae, which have the most advanced jaws.

Subfamilies and genera

Loricariidae is divided into the following subfamilies and genera:

Subfamily Lithogeninae Gosline, 1947
* Lithogenes C. H. Eigenmann, 1909
Subfamily Delturinae Reis, E. H. L. Pereira & Armbruster, 2006
* Delturus C. H. Eigenmann & R. S. Eigenmann 1889
* Hemipsilichthys C. H. Eigenmann & R. S. Eigenmann, 1889
Subfamily Rhinelepinae Armbruster, 2004
* Pogonopoma Regan, 1904
* Pseudorinelepis Bleeker, 1862
* Rhinelepis Agassiz, 1829
Subfamily Loricariinae Rafinesque, 1815
* Brochiloricaria Isbrücker & Nijssen, 1979
* Cheilonimata Provenzano, 2023
* Crossoloricaria Isbrücker, 1979
* Cteniloricaria Isbrücker & Nijssen, 1979
* Dasyloricaria Isbrücker & Nijssen, 1979
* Dentectus Martín Salazar, Isbrücker & Nijssen 1982
* Farlowella C. H. Eigenmann & R. S. Eigenmann, 1889
* Fonchiiloricaria Rodriguez, Ortega & Covain, 2011
* Furcodontichthys Rapp Py-Daniel, 1981
* Harttia Steindachner, 1877
* Harttiella Boeseman, 1971
* Hemiodontichthys Bleeker, 1862
* Lamontichthys P. Miranda Ribeiro, 1939
* Limatulichthys Isbrücker & Nijssen, 1979
* Loricaria Linnaeus, 1758
* Loricariichthys Bleeker, 1862
* Metaloricaria Isbrücker, 1975
* Paraloricaria Isbrücker, 1979
* Planiloricaria Isbrücker 1971
* Proloricaria Isbrücker, 2001
* Pseudohemiodon Bleeker, 1862
* Pseudoloricaria Bleeker, 1862
* Pterosturisoma Isbrücker & Nijssen, 1978
* Pyxiloricaria Isbrücker & Nijssen, 1984
* Reganella C. H. Eigenmann, 1905
* Rhadinoloricaria Isbrücker & Nijssen, 1974
* Ricola Isbrücker & Nijssen, 1978
* Rineloricaria Bleeker, 1862
* Spatuloricaria Schultz, 1944
* Sturisoma Swainson, 1838
* Sturisomatichthys Isbrücker & Nijssen, 1979
Subfamily Hypoptopomatinae C. H. Eigenmann & R. S. Eigenmann, 1890
* Acestridium Haseman, 1911
* Chauliocheilos Martins, Andrade, Rosa & Langeani, 2014
* Corumbataia Britski, 1997
* Curculionichthys Roxo, Silva, Ochoa & Oliveira, 2015
* Epactionotus Reis & Schaefer, 1998
* Eurycheilichthys Reis & Schaefer, 1993
* Euryochus E. H. L. Pereir & Reis, 2017
* Hirtella E. H. L. Pereira, Zanata, Cetra & Reis, 2014
* Hisonotus C. H. Eigenmann & R. S. Eigenmann, 1889
* Hypoptopoma Günther, 1868
* Isbrueckerichthys Derijst, 1996
* Kronichthys A. Miranda Ribeiro, 1908
* Lampiella Isbrücker, 2001
* Leptotocinclus Delapieve, Lehmann A & Reis, 2018
* Microlepidogaster C. H. Eigenmann & R. S. Eigenmann, 1889
* Nannoptopoma Schaefer, 1996
* Nannoxyropsis Delapieve, Lehmann A & Reis, 2018
* Niobichthys Schaefer & Provenzano, 1998
* Otocinclus Cope, 1871
* Otothyris Myers, 1927
* Otothyropsis Ribeiro, Carvalho & A. Melo, 2005
* Oxyropsis C. H. Eigenmann & R. S. Eigenmann, 1889
* Pareiorhaphis A. Miranda Ribeiro, 1918
* Pareiorhina Gosline, 1947
* Parotocinclus C. H. Eigenmann & R. S. Eigenmann, 1889
* Plesioptopoma Reis, Pereira & Lehmann A., 2012
* Pseudotocinclus Nichols, 1919
* Pseudotothyris Britski & Garavello, 1984
* Rhinolekos Martins & Langeani. 2011
* Rhinotocinclus Reis & Lehmann A., 2022
* Schizolecis Britski & Garavello, 1984
Subfamily Hypostominae Kner, 1853
* Acanthicus Agassiz, 1829
* Ancistomus Isbrücker & Seidel, 2001
* Ancistrus Kner, 1854
* Andeancistrus Lujan, Meza-Vargas & Barriga Salazar, 2015
* Aphanotorulus Isbrücker & Nijssen, 1983
* Araichthys Zawadzki, Bifi & Mariotto, 2016
* Avalithoxus Lujan, Armbruster & Lovejoy, 2018
* Baryancistrus Rapp Py-Daniel, 1989
* Chaetostoma Tschudi, 1846
* Colossimystax Armbruster & Lujan, 2025
* Corymbophanes C. H. Eigenmann, 1909. Loricariidae: Hypostominae.
* Cordylancistrus Isbrücker, 1980
* Cryptancistrus Fisch-Muller, Mol & Covain, 2018
* Dekeyseria Rapp Py-Daniel, 1985
* Dolichancistrus Isbrücker, 1980
* Exastilithoxus Isbrücker & Nijssen, 1979
* Guyanancistrus Isbrücker, 2001
* Hemiancistrus Bleeker, 1862
* Hopliancistrus Isbrücker & Nijssen, 1989
* Hypancistrus Isbrücker & Nijssen, 1991
* Hypostomus Lacepède, 1803
* Isorineloricaria Isbrücker, 1980
* Lasiancistrus Regan, 1904
* Leporacanthicus Isbrücker & Nijssen, 1989
* Leptoancistrus Meek & Hildebrand, 1916
* Lithoxancistrus Isbrücker, Nijssen & Cala, 1988
* Lithoxus C. H. Eigenmann, 1910
* Megalancistrus Isbrücker, 1980
* Neblinichthys Ferraris, Isbrücker & Nijssen, 1986
* Panaqolus Isbrücker & Schraml, 2001
* Panaque C. H. Eigenmann & R. S. Eigenmann, 1889
* Paralithoxus Boeseman, 1982
* Parancistrus Bleeker, 1862
* Paulasquama Armbruster & Taphorn, 2011
* Peckoltia A. Miranda Ribeiro, 1912
* Peckoltichthys A. Miranda Ribeiro, 1917
* Pseudacanthicus Bleeker, 1862
* Pseudancistrus Bleeker, 1862
* Pseudolithoxus Isbrücker & Werner, 2001
* Pseudoqolus Lujan, Cramer, Covain, Fisch-Muller & López-Fernández, 2017
* Pterygoplichthys Gill, 1858
* Scobinancistrus Isbrücker & Nijssen, 1989
* Spectracanthicus Nijssen & Isbrücker, 1987
* Stellantia Armbruster & Lujan, 2025
* Transancistrus Lujan, Meza-Vargas & Barriga Salazar, 2015
* Yaluwak Lujan & Armbruster, 2019