View source for Callichthys

{{Short description|Genus of fishes}}
{{Automatic taxobox
| image = Callichthys callichthys.JPG
| image_upright = 1.15
| image_caption = Cascarudo (''[[Callichthys callichthys]]'').
| taxon = Callichthys
| authority = [[Giovanni Antonio Scopoli|Scopoli]] (ex [[Laurence Theodore Gronow|Gronow]]), 1777
| type_species = ''[[Callichthys callichthys]]''
| type_species_authority = [[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]
| subdivision_ranks = Species
| subdivision = 
}}

'''''Callichthys''''' is a small [[genus]] of [[freshwater]] [[catfish]] in the Callichthyinae subfamily of the [[Callichthyidae|armored catfish]] family, and consists of 4 species from [[South America]]. The genus ''Callichthys'' is distributed in most freshwater drainages of [[South America]].<ref>{{cite web|url=http://www.tolweb.org/Callichthys/15340|title=Callichthys|last=Reis|first=Roberto E.|authorlink=Roberto Esser dos Reis|date=1996-04-29|publisher=[[Tree of Life Web Project]]|accessdate=2007-07-12}}</ref>

==Taxonomy==
The [[biological type|type species]] for this genus is ''[[Callichthys callichthys|Callichtys callichthys]]''.  The name ''Callichthys'' is derived from the [[Greek language|Greek]] ''kallos'' (beautiful) and ''ichthys'' (fish).<ref name=fishbase>{{FishBase genus | genus = Callichthys | year = 2011 | month = December}}</ref> 3 of the 4 species were described only relatively recently.<ref name="Lehmann">{{cite journal|journal=[[Copeia]]|year=2004|issue=2|pages=336–343|title=''Callichthys serralabium'': A New Species of Neotropical Catfish from the Upper Orinoco and Negro Rivers (Siluriformes: Callichthyidae)|editor1-first=J. W.|first=Pablo|editor1-last=Armbruster|last=Lehmann A.|author2=Reis, Roberto E. |authorlink2=Roberto Esser dos Reis |doi=10.1643/CI-03-129R|volume=2004}}</ref>

The genus ''Callichthys'' is in need of taxonomic work, as it includes 13 nominal species but specimens of this genus are usually referred to as ''C. callichthys'' regardless of collecting locality.<ref name="Lehmann"/>

According to a 1997 paper, ''Callichthys'' is the most [[Basal (phylogenetics)|basal]] member of the subfamily.<ref>{{Cite journal |last=Lehmann A |first=Pablo |last2=Reis |first2=Roberto E. |date=2004 |editor-last=Armbruster |editor-first=J. W. |title=Callichthys serralabium: A New Species of Neotropical Catfish from the Upper Orinoco and Negro Rivers (Siluriformes: Callichthyidae) |url=http://www.bioone.org/doi/abs/10.1643/CI-03-129R |journal=Copeia |language=en |volume=2004 |issue=2 |pages=336–343 |doi=10.1643/CI-03-129R |issn=0045-8511|url-access=subscription }}</ref> In a 2004 study, different relationships among the callichthyines were found: ''Dianema'' and ''Hoplosternum'' form the most basal clade, and ''Callichthys'' is [[Cladistics|sister]] to ''Lepthoplosternum'' and ''Megalechis''.<ref>{{Cite journal |last=Reis |first=Roberto E. |last2=Kaefer |first2=Cintia C. |date=2005 |editor-last=Armbruster |editor-first=J. W. |title=Two New Species of the Neotropical Catfish Genus Lepthoplosternum (Ostariophysi: Siluriformes: Callichthyidae) |url=http://www.bioone.org/doi/abs/10.1643/0045-8511%282005%29005%5B0724%3ATNSOTN%5D2.0.CO%3B2 |journal=Copeia |language=en |volume=2005 |issue=4 |pages=724–731 |doi=10.1643/0045-8511(2005)005[0724:TNSOTN]2.0.CO;2 |issn=0045-8511|url-access=subscription }}</ref>

== Species ==
There are currently four recognized species in this genus:<ref name=fishbase/>
*''[[Callichthys callichthys]]'' <small>([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])</small> (Cascarudo)
*''[[Callichthys fabricioi]]'' <small>[[César Román-Valencia|Román-Valencia]], [[Pablo Cesar Lehmann-Albornoz|Lehmann A.]] & [[Ana Milena Muñoz|Muñoz]], 1999</small>
*''[[Callichthys oibaensis]]'' <small>[[Carlos Arturo Ardila Rodríguez|Ardila Rodríguez]], 2006</small>
*''[[Callichthys serralabium]]'' <small>[[Pablo Cesar Lehmann-Albornoz|Lehmann A.]] & [[Roberto Esser dos Reis|R. E. dos Reis]], 2004</small>

==Description==
The genus ''Callichthys'' can be readily distinguished from other callichthyids by having the [[coracoid]]s covered by skin and not exposed ventrally, the [[infraorbital bone|infraorbital]] bones also covered by skin, and the head highly depressed with less than 75% of the [[cleithrum|cleithral]] width (except sometimes in mature males).<ref name="Lehmann"/>

==Ecology==
''Callichthys'' is normally found in large schools on the muddy bottoms of slow-moving rivers, pools, drainage ditches, and swampy areas.  In water with low oxygen content, the fish are capable of utilizing atmospheric air by taking in a gulp of air at the surface of the water and passing it back to the hind gut.  The walls of the gut are lined with tiny blood vessels into which the oxygen from the air can pass, similar to the function of true lungs.  The remaining gasses pass out through the anus.   When there is a severe drought, these air breathers are  able to traverse short stretches of land seeking better conditions.   The fish is also capable of making sounds, both grunts and squeaks.

==In the aquarium==
Spawning has been accomplished in the aquarium.  ''Callichthys'' is a builder of [[bubblenest]]s from plant parts, some bottom materials, and bubbles formed by a mouth secretion and air.  The male forms a mass of bubbles about 20&nbsp;cm (8&nbsp;in) in diameter and 10&nbsp;cm (4&nbsp;in) high.  During the time of construction, the female is actively chased away or ignored.   When the nest construction is complete, the male will accept the female.   The eggs (up to several hundred) are deposited into the nest and the male or the pair will actively protect the nest for about four weeks until the [[Fry (biology)|fry]] come out of the nest at the size of 2.5&nbsp;cm (1&nbsp;in).

==References==
<references/>
*{{cite book | title = A Complete Introduction to Corydoras and Related Catfishes | last = Burgess | first = Dr. Warren E. | publisher = T.F.H. Publications | location = Neptune City, NJ | year = 1987 | isbn = 0-86622-264-2 }}

{{Taxonbar|from=Q1758830}}

[[Category:Callichthys| ]]
[[Category:Callichthyidae]]
[[Category:Catfish genera]]
[[Category:Taxa named by Giovanni Antonio Scopoli]]
[[Category:Freshwater fish genera]]