Jump to content

Loricariidae

From Wikipedia, the free encyclopedia
(Redirected fromOmega iris)

Loricariidae
Temporal range:Late Oligocene–Present[1]PossibleCenomanianrecord[2]
Loricaria simillima
Scientific classificationEdit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Superfamily: Loricarioidea
Family: Loricariidae
Rafinesque,1815
Subfamilies

Genus†Afrocascudo?
Delturinae
Hypoptopomatinae
Hypostominae
Lithogeneinae
Loricariinae
Neoplecostominae
Otothyrinae(sometimes included in Hypoptopomatinae)
GenusNannoplecostomus(incertae sedis)[3]

Loricariidaeis the largestfamilyofcatfish(order Siluriformes), with over 90generaand just over 680species.[4]Loricariids originate fromfreshwaterhabitats ofCosta Rica,Panama,and tropical and subtropicalSouth America.These fish are noted for the bony plates covering their bodies and theirsuckermouths.Severalgeneraare sold as "plecos",notably the suckermouth catfish,Hypostomus plecostomus,and are popular asaquariumfish.

Common names

[edit]

Members of the family Loricariidae are commonly referred to as loricariids, suckermouth catfishes,armoured catfish,or suckermouth armoured catfish.[4]The name "plecostomus",and its shortened forms" pleco "and" plec ", are used for many Loricariidae, sincePlecostomus plecostomus(now calledHypostomus plecostomus) was one of the first loricariid species imported for the fish-keeping hobby.[5]

Some loricariids are not normally considered "plecostomus", such asFarlowellacatfish.

In their nativerange,these fish are known ascascudosoracarís.[6]

L-numbers

[edit]
Main article:L-number

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 beentaxonomically 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.[7]In some cases, two different L-numbered catfish have turned out to be different populations of the same species, while in other cases, multiple (but superficially similar) species have all been traded under a single L-number.[citation needed]

Taxonomy and evolution

[edit]

Because of their highly specialized morphology, loricariids have been recognized as amonophyleticassemblage in even the earliest classifications of the Siluriformes, meaning they consist of a natural grouping with a common ancestor and all of its descendants.[8]Loricariidae is one of seven families in the superfamilyLoricarioidea,along withAmphiliidae,Trichomycteridae,Nematogenyidae,Callichthyidae,Scoloplacidae,andAstroblepidae.Some of these families also exhibit suckermouths or armor, although never in the same individual, as in loricariids.[4]

This is the largestcatfishfamily, including about 684 species in around 92 genera, with new species being described each year.[4]However, this family is in flux, and revisions are likely.[4]For example, the subfamily Ancistrinae is accepted as late as the 2006 edition of Nelson'sFishes of the World;it later becomes grouped as a tribe, because of its recognition as asister groupto the Pterygoplichthyini.[4][6][9]Under Ambruster, six subfamilies are recognized:Delturinae,Hypoptopomatinae,Hypostominae,Lithogeneinae,Loricariinae,andNeoplecostominae.[9][10]

Monophyly for the family is strongly supported, except, possibly, the inclusion ofLithogenes.[11]Lithogenesis the only genus within the subfamily Lithogeneinae. This genus and subfamily, the mostbasalgroup in Loricariidae, is thesister groupto the rest of the family.[12]Neoplecostominae are the most basal group among the loricariids with the exception of Lithogeneinae.[13]However, the genera of Neoplecostominae do not appear to form a monophyletic assemblage.[14]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.[11]The Hypostominae are the largest subfamily of Loricariidae. It is made up of fivetribes.Four of the five tribes,Corymbophanini,Hypostomini,Pterygoplichthyini,andRhinelepini,include about 24 genera. The fifth and largest tribe,Ancistrini(formerly recognized as its own subfamily), includes 30 genera.[15]

Loricariidfossilsare extremely rare. The earliest known definitive taxon isTaubateiafrom theLate Oligocene-Early MioceneinBrazil.[1]The putativeCenomanianmemberAfrocascudo,initially described as the earliest loricariid catfish in 2024,[2]might represent a juvenileobaichthyidlepisosteiform,possibly a junior synonym ofObaichthys,[16]though this has been disputed based on the complete ossification of the bones indicating full maturity and the absence of importantholosteancharacters.[17]Within the superfamilyLoricarioidea,the Loricariidae are the mostderived;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.[18]

Distribution and habitat

[edit]

The family Loricariidae is vastly distributed over both the east and west sides of theAndesmountains, however, most species are generally restricted to small geographic ranges.[19]They are primarily found infreshwaterhabitats ofSouth America,but severalloricariinesandhypostominesare native toPanama,and two species (Fonchiiichthys uracanthusandHemiancistrusaspidolepis) are native toCosta Rica.[20]Species occur in swift-flowing streams from the lowlands up to 3,000 m (9,800 ft) in elevation.[4]They can also be found in a variety of other freshwater environments.[5]They can be found in torrential mountain rivers, quiet brackish estuaries,black acidic waters,and even in subterranean habitats.[8]

Description and biology

[edit]

This family has extremely variable color patterns and body shapes.[8]Loricariids are characterized by bony plates covering their bodies, similar to the bony plates incallichthyids.(InLatin,loricameanscorselet).[21]These fish exhibit aventralsuckermouth, withpapillae(small projections) on the lips. When present, theadipose finusually has a spine at the forward edge.[4]These fish have, when they are present, a unique pair ofmaxillary barbels.[4][8]These fish have relatively long intestines due to their usuallyherbivorousordetrivorousdiets.[4]The body is characteristically flattened in this family.[8]Taste budscover almost the entire surface of the body and fin spines.[22]Body lengths can range from 2.22 cm (0.87 in) inNannoplecostomus eleonoraeto over 100 cm (39 in) inPanaque,Acanthicus,andPterygoplichthys.[19]

One of the most obvious characteristics of the loricariids is thesuckermouth.The modified mouth and lips allow the fish to feed, breathe, and attach to the substrate through suction. The lips were once believed to be unable to function as a sucker while respiration continued, as the inflowing water would cause the system to fail; however, respiration and suction can function simultaneously. Inflowing water passing under the sucker is limited to a thin stream immediately behind each maxillary barbel; themaxillaein loricariids support only small maxillary barbels and are primarily used to mediate the lateral lip tissue in which they are embedded, preventing failure of suction during inspiration[vague].To achieve suction, the fish presses its lips against the substrate and expands its oral cavity, causing negative pressure.[23]

Also, unlike most other catfishes, thepremaxillaeare highly mobile, and the lower jaws have evolved towards a medial position, with the teeth pointedrostroventrally;these are important evolutionary innovations.[18]The fish rotates its lower and upper jaws to scrape the substrate. Of the two, the lower jaws are more mobile.[23]

Loricariid catfishes have evolved several modifications of their digestive tracts that function as accessoryrespiratory organsorhydrostaticorgans. These complex structures would have been independently evolved a number of times within the family. This includes an enlarged stomach in the Pterygoplichthyini,Hypostomus,andLithoxus,a U-shapeddiverticulumin Rhinelepini, and a ring-like diverticulum inOtocinclus.It may be noted that even loricariids with unmodified stomachs have a slight ability to breathe air.[24]

Considerablesexual dimorphismoccurs in this family, most pronounced during the breeding season. For example, inLoricariichthys,the male has a large expansion of its lower lip, which it uses to hold a clutch of eggs.[22]Ancistrusmales have snouts with fleshy tentacles.[22]In loricariids,odontodesdevelop almost anywhere on the external surface of the body and first appear soon after hatching; odontodes appear in a variety of shapes and sizes and are often sexually dimorphic, being larger in breeding males.[22]In mostAncistrinispecies, sharp evertible cheek spines (elongated odontodes) are often more developed in males and are used in intraspecific displays and combat.[22]

Omega iris

[edit]
The Omega iris allows loricariids to adjust the amount of light that enters their eye.

Unusual forbony fish,many species have a modifiediriscalled anOmega iris.The dorsal segment of the iris expands downward over the pupil to form a loop which can expand and contract, called an iris operculum; when light levels are high, the pupil reduces in diameter and the loop expands to cover the center of the pupil, giving rise to acrescent-shaped, light-transmitting partial pupil.[25]This feature gets its name from its similarity to an upside-down uppercaseGreek letterOmega(Ω). The origins of this structure are unknown, but breaking up the outline of the highly visible eye has been suggested to aidcamouflagein what are often highly mottled animals.[25]Species in the tribeRhinelepiniare an exceptional group among loricariids, having a circular iris.[26]The presence or absence of the iris operculum can be used for identification of species in the subfamilyLoricariinae.[8]

Genetics

[edit]

As of 2000, only 56 loricariid species have been cytogenically investigated.[6]The basaldiploidnumber ofchromosomesis 2n = 54 in this family,[27]but with a wide variation in the chromosome number in this fish group, ranging from 2n = 36 in theLoricariinae,Rineloricaria latirostris,to 2n = 96 in a species ofUpsilodus(Hemipsilichthys).[27]Most members of the Ancistrini and Pterygoplichthyini have 52 chromosomes.[6]Karyotypic evolution by means ofcentric fusionsandcentric fissionsseems to be a common feature among loricariids; this is demonstrated by a higher number of biarmed chromosomes in species with lower diploid number and many uniarmed chromosomes in species with higher diploid numbers.[28]Studies conducted with representatives of some genera of Hypostominae showed, within this group, thediploid numberranges from 2n = 52 to 2n = 80. However, the supposed wide karyotypic diversity the family Loricariidae or the subfamily Hypostominae would present is almost exclusively restricted to the genusHypostomus,and the species from the other genera had a conserved diploid number.[13]In some species, there is a ZZ/ZWsex-determination system.[6][28]

Ecology

[edit]
Panaque nigrolineatusattached to a piece of wood

The suckermouth exhibited by these catfish allows them to adhere to objects in their habitats, even in fast-flowing waters.[8]The mouth and teeth also are adapted to feed on a variety of foods, such asalgae,invertebrates,anddetritus.[8]Some species, notably thePanaque,are known forxylophagy,or the ability to digestwood.[29]

Most species of loricariids arenocturnal animals.Some species areterritorial,while others, such asOtocinclus,prefer to live in groups.[5]

Air-breathing is well known among many loricariids; this ability is dependent on the risk ofhypoxiafaced by a species; torrent-dwelling species tend to have no ability to breathe air, while low-land, pool-dwelling species, such as those ofHypostomus,have a great ability to breathe air.[24]Pterygoplichthysis known for being kept out of water and sold alive in fish markets, surviving up to 30 hours out of water.[24]Loricariids are facultative air breathers; they will only breathe air if under stress and will only use their gills in situations when oxygen levels are high. The dry season is a likely time for this; there would be little food in the stomach, which would allow its use for air breathing.[24]

Loricariids exhibit a wide range of reproductive strategies, including cavity spawning, attachment of eggs on the underside of rocks, and egg-carrying.[22]Parental care is usually good, and the male guards the eggs and sometimes the larvae.[22]The eggs hatch after four to 20 days, depending on the species.[5]

Three species known from subterranean habitats are truetroglobiteswith reducedpigmentation(appearing overall whitish) and eyes:Ancistruscryptophthalmus,A. galaniandA. formoso.[30][31][32]Similar adaptions with reduced pigmentation are known from two loricariids found in deep water in largeAmazonianrivers,Peckoltia pankimpujuandPanaque bathyphilus.[33]

In the aquarium

[edit]
Pterygoplichthys multiradiatus,often sold as acommon pleco,is an aquarium fish often purchased as analgae eater.

Loricariids are popularaquariumfish, where they are often sold as "plecs", "plecos" or "plecostomus".[4]These fish are often purchased because of theiralgae-eatinghabits, though this role may not be carried out.[5]Loricariid are eithervegetarian,omnivore,carnivoreorwood-eaters.[34]A great many species of loricariids are also sold for their ornamental qualities, representing many body shapes and colors.

Most species of loricariids are nocturnal and will shy away from bright light, appreciating some sort of cover to hide under throughout the day. As they often originate from habitats with fast-moving water,filtrationshould be vigorous.[5]

A number of species of loricariids have been bred in captivity.[5]

References

[edit]
  1. ^abMalabarba, Maria Claudia; Lundberg, John G. (2007)."A fossil loricariid catfish (Siluriformes: Loricarioidea) from the Taubaté Basin, eastern Brazil".Neotropical Ichthyology.5(3): 263–270.doi:10.1590/S1679-62252007000300005.
  2. ^abBrito, P. M.; Dutheil, D. B.; Gueriau, P.; Keith, P.; Carnevale, G.; Britto, M.; Meunier, F. J.; Khalloufi, B.; King, A.; de Amorim, P. F.; Costa, W. J. E. M. (2024). "A saharan fossil and the dawn of Neotropical armoured catfishes in Gondwana".Gondwana Research.132:103–112.doi:10.1016/j.gr.2024.04.008.
  3. ^Ribeiro, Alexandre C.; Lima, Flávio C. T.; Pereira, Edson H. L. (2012). "A New Genus and Species of a Minute Suckermouth Armored Catfish (Siluriformes: Loricariidae) from the Rio Tocantins Drainage, Central Brazil: The Smallest Known Loricariid Catfish".Copeia.2012(4): 637–647.doi:10.1643/ci-11-137.S2CID84436639.
  4. ^abcdefghijkNelson, Joseph, S. (2006).Fishes of the World.John Wiley & Sons, Inc.ISBN978-0-471-25031-9.{{cite book}}:CS1 maint: multiple names: authors list (link)
  5. ^abcdefgFenner, Robert."Loricariids".WetWebMedia.Retrieved2007-05-03.
  6. ^abcdede Oliveira, Renildo Ribeiro; Souza, Issakar Lima Souza; Venere, Paulo Cesar (2006)."Karyotype description of three species of Loricariidae (Siluriformes) and occurrence of the ZZ/ZW sexual system inHemiancistrus spilommaCardoso & Lucinda, 2003 "(PDF).Neotropical Ichthyology.4(1): 93–97.doi:10.1590/s1679-62252006000100010.
  7. ^Linder, Shane."What are L Numbers?".Archived fromthe originalon 2006-04-22.
  8. ^abcdefghCovain, Raphael; Fisch-Muller, Sonia (2007)."The genera of the Neotropical armored catfish subfamily Loricariinae (Siluriformes: Loricariidae): a practical key and synopsis"(PDF).Zootaxa.1462:1–40.doi:10.11646/zootaxa.1462.1.1.Retrieved2009-06-23.
  9. ^abJ. W. Armbruster."Loricariid taxa list".
  10. ^Reis, Roberto E.;Pereira, Edson H.L.; Armbruster, Jonathan W. (2006)."Delturinae, a new loricariid catfish subfamily (Teleostei, Siluriformes), with revisions ofDelturusandHemipsilichthys".Zoological Journal of the Linnean Society.147(2): 277–299.doi:10.1111/j.1096-3642.2006.00229.x.
  11. ^abFerraris, Carl J. Jr. (2007)."Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types"(PDF).Zootaxa.1418:1–628.CiteSeerX10.1.1.232.798.doi:10.11646/zootaxa.1418.1.1.Retrieved2009-06-23.
  12. ^Schaefer, Scott A. (2003)."Relationships ofLithogenes villosusEigenmann, 1909 (Siluriformes, Loricariidae): Evidence from High-Resolution Computed Microtomography "(PDF).American Museum Novitates(3401). American Museum of Natural History: 1–55.doi:10.1206/0003-0082(2003)401<0001:ROLVES>2.0.CO;2.hdl:2246/2827.S2CID36180254.
  13. ^abAlves, Anderson Luís; Oliveira, Claudio; Foresti (2005). "Comparative cytogenetic analysis of eleven species of subfamilies Neoplecostominae and Hypostominae (Siluriformes: Loricariidae)".Genetica.124(2–3): 127–136.doi:10.1007/s10709-004-7561-4.PMID16134327.S2CID8239240.
  14. ^Pereira, Edson H. Lopes (2005)."Resurrection ofPareiorhaphisMiranda Ribeiro, 1918 (Teleostei: Siluriformes: Loricariidae), and description of a new species from the Rio Iguaçu basin, Brazil ".Neotropical Ichthyology.3(2): 271–276.doi:10.1590/S1679-62252005000200004.
  15. ^Werneke, David C.; Armbruster, Jonathan W.; Lujan, Nathan K.; Taphorn, Donald C. (2005)."Hemiancistrus guahiborum,a new suckermouth armored catfish from Southern Venezuela (Siluriformes: Loricariidae) ".Neotropical Ichthyology.3(4). Sociedade Brasileira de Ictiologia: 543–548.doi:10.1590/S1679-62252005000400012.
  16. ^Britz, R.; Pinion, Amanda K.; Kubicek, Kole M.; Conway, Kevin W. (2024). "Comment on" A Saharan fossil and the dawn of Neotropical armoured catfishes in Gondwana "by Brito et al".Gondwana Research.doi:10.1016/j.gr.2024.06.014.
  17. ^Brito, Paulo M.; Dutheil, Didier B.; Keith, Philippe; Carnevale, Giorgio; Meunier, François J.; Khalloufi, Bouziane; Gueriau, Pierre (2024). "A reply to a comment on Brito et al., 2024, A Saharan fossil and the dawn of the Neotropical armoured catfishes in Gondwana by Britz, Pinion, Kubicek and Conway".Gondwana Research.doi:10.1016/j.gr.2024.06.013.
  18. ^abSchaefer, Scott A.; Lauder, George V. (1986). "Historical Transformation of Functional Design: Evolutionary Morphology of Feeding Mechanisms in Loricarioid Catfishes".Systematic Zoology.35(4). Society of Systematic Biologists: 489–508.doi:10.2307/2413111.JSTOR2413111.S2CID86178220.
  19. ^abQuevedo, Rodrigo;Reis, Roberto E.(2002). Schaefer, S. A. (ed.)."Pogonopoma obscurum:A New Species of Loricariid Catfish (Siluriformes: Loricariidae) from Southern Brazil, with Comments on the GenusPogonopoma"(PDF).Copeia.2002(2): 402–410.doi:10.1643/0045-8511(2002)002[0402:POANSO]2.0.CO;2.S2CID85769730.
  20. ^Angulo, Arturo; Garita-Alvarado, Carlos A.; Bussing, William A.; López, Myrna I. (2013)."Annotated checklist of the freshwater fishes of continental and insular Costa Rica: Additions and nomenclatural revisions".Check List.9(5): 987–1019.doi:10.15560/9.5.987.
  21. ^Froese, Rainer;Pauly, Daniel (eds.)."Family Loricariidae".FishBase.December 2011 version.
  22. ^abcdefgSabaj, Mark H.; Armbruster, Jonathan W.; Page, Lawrence M. (1999)."Spawning inAncistrus(Siluriformes: Loricariidae) with comments on the evolution of snout tentacles as a novel reproductive strategy: larval mimicry "(PDF).Ichthyol. Explor. Freshwaters.10(3): 217–229.Retrieved2009-06-23.
  23. ^abGeerinckx, Tom; Brunain, Marleen; Herrel, Anthony; Aerts, Peter; Adriaens, Dominique (January 2007)."A head with a suckermouth: a functional-morphological study of the head of the suckermouth armoured catfishAncistruscf.triradiatus(Loricariidae, Siluriformes) "(PDF).Belg. J. Zool.137(1): 47–66. Archived fromthe original(PDF)on 2007-09-27.Retrieved2007-07-24.
  24. ^abcdArmbruster, Jonathan W. (1998)."Modifications of the Digestive Tract for Holding Air in Loricariid and Scoloplacid Catfishes"(PDF).Copeia.1998(3): 663–675.doi:10.2307/1447796.JSTOR1447796.Retrieved2009-06-23.
  25. ^abDouglas, Ron H.; Collin, Shaun P.; Corrigan, Julie (2002-11-15)."The eyes of suckermouth armoured catfish (Loricariidae, subfamily Hypostomus): pupil response, lenticular longitudinal spherical aberration and retinal topography"(PDF).Journal of Experimental Biology.205(22). The Journal of Experimental Biology: 3425–3433.doi:10.1242/jeb.205.22.3425.PMID12364396.
  26. ^Armbruster, Jonathan W. (1998). "Phylogenetic Relationships of the Suckermouth Armored Catfishes of the Rhinelepis Group (Loricariidae: Hypostominae)".Copeia.1998(3): 620–636.doi:10.2307/1447792.JSTOR1447792.
  27. ^abArtoni, Roberto Ferreira; Bertollo, Luiz Antonio Carlos (2001)."Trends in the karyotype evolution of Loricariidae fish (Siluriformes)".Hereditas.134(3): 201–210.doi:10.1111/j.1601-5223.2001.00201.x.PMID11833282.
  28. ^abKavalco, KF; Pazza, R; Bertollo, LAC; Moreira-Filho, O (2005)."Karyotypic diversity and evolution of Loricariidae (Pisces, Siluriformes)"(PDF).Heredity.94(2): 180–186.doi:10.1038/sj.hdy.6800595.PMID15562288.S2CID6149247.Retrieved2009-06-23.
  29. ^Nelson, J. A.;Wubah, D. A.;Whitmer, M. E.; Johnson, E. A.; Stewart, D. J. (1999). "Wood-eating catfishes of the genusPanaque:gut microflora and cellulolytic enzyme activities ".Journal of Fish Biology.54(5): 1069–1082.doi:10.1111/j.1095-8649.1999.tb00858.x.
  30. ^Romero, A., editor (2001).The Biology of Hypogean Fishes.Developments in Environmental Biology of Fishes.ISBN978-1402000768
  31. ^Sabino, J., and E. Trajano (1997).A new species of blind armoured catfish, genus "Ancistrus", from caves of Bodoquena region, Mato Grosso do Sul, southwestern Brazil (Siluriformes, Loricariidae, Ancistrinae).Revue française d'Aquariologie Herpétologie24(3-4): 73–78
  32. ^
    • Trajano, E (2001). "Habitat and population data of troglobitic armored cave catfish,Ancistrus cryptophthalmusReis, 1987, from central Brazil (Siluriformes: Loricariidae) ". In Aldemaro Romero (ed.).The biology of hypogean fishes.Developments in environmental biology of fishes. Vol. 21. pp. 195–200.doi:10.1007/978-94-015-9795-1_14.ISBN978-90-481-5848-5.
    • Trajano, E (2001). "Habitat and population data of troglobitic armored cave catfish,Ancistrus cryptophthalmusReis, 1987, from central Brazil (Siluriformes: Loricariidae) ".Environmental Biology of Fishes.62(1–3): 195–200.doi:10.1023/A:1011884829498.
  33. ^Lujan, N.K., and C. Chamon (2008).Two new species of Loricariidae (Teleostei: Siluriformes) from main channels of the upper and middle Amazon Basin, with discussion of deep water specialization in loricariids. Ichthyological Exploration of Freshwaters. 19: 271–282.
  34. ^"Feeding Plecos, Part 2 • Who eats what?".Planetcatfish.Retrieved2022-02-11.
[edit]
Wikispecieshas information related toLoricariidae.
Wikimedia Commons has media related toLoricariidae.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Loricariidae&oldid=1231577433#Description_and_biology"