Porthole shovelnose catfish

Taxobox
name = Porthole shovelnose catfish
regnum = Animalia
phylum = Chordata
classis = Actinopterygii
ordo = Siluriformes
familia = Pimelodidae
genus = "Hemisorubim"
genus_authority = Bleeker, 1862
species = "H. platyrhynchos"
binomial = "Hemisorubim platyrhynchos"
binomial_authority = (Valenciennes in Cuvier and Valenciennes, 1840)
synonyms ="Platystoma platyrhynchos"
Valenciennes, 1840

The porthole shovelnose catfish or spotted shovelnose catfish, "Hemisorubim platyrhynchos", is the only species in the genus "Hemisorubim" of the catfish (order Siluriformes) family Pimelodidae. [ITIS|ID=681749|taxon="Hemisorubim platyrhynchos"|year=2007|month=May]

Taxonomy

This fish is considered one of the "sorubimine" catfishes, an informal group of catfish that includes genera such as "Sorubim", "Pseudoplatystoma", and "Brachyplatystoma".cite journal|url=http://www.bioone.org/archive/0045-8511/2005/3/pdf/i0045-8511-2005-3-492.pdf|title="Brachyplatystoma capapretum": a New Species of Goliath Catfish from the Amazon Basin, with a Reclassification of Allied Catfishes (Siluriformes: Pimelodidae)|journal=Copeia|format=PDF|year=2005|pages=492 – 516|issue=3|last=Lundberg|first=John G.|coauthors=Akama, Alberto|doi=10.1643/CI-04-036R1|volume=2005] This genus forms a monophyletic group with "Sorubim", "Sorubimichthys", "Pseudoplatystoma", and "Zungaro". Of these genera, "Hemisorubim" is most closely related to "Pseudoplatystoma".cite journal|url=http://www.accefyn.org.co/PubliAcad/Periodicas/Volumen30/114/114_117_141.pdf|title=Anatomía Comparada y Evolución de las Especies de "Pseudoplatystoma" Bleeker 1862 (Siluriformes: Pimelodidae)|first=Uriel Ángel|last=Buitrago-Suárez|journal=Rev. Acad. Colomb. Cienc.|volume=30|issue=114|pages=117–141|year=2006|format=PDF]

Distribution

This species is native to South America and originates from the Amazon, Maroni, Orinoco, and Paraná River basins. It also occurs in the Pantanal.cite journal|url=http://www.scielo.br/pdf/bjb/v64n4/22983.pdf|title=Age and Growth of the Porthole Shovelnose Catfish ("Hemisorubim platyrhynchos") in the Pantanal|last=Penha|first=J. M. F.|coauthors=Mateus, L. A. F.; Barbieri, G.|journal=Braz. J. Biol.|volume=64|issue=4|pages=833–840|year=2004|format=PDF|doi=10.1590/S1519-69842004000500013]

Appearance and anatomy

This fish reaches a length of 53centimetres (20in) SL and up to 1,470 grams (3.23 lb).FishBase species|genus=Hemisorubim|species=platyrhynchos|year=2007|month=May] It is the sixth largest Pimelodid in the Pantanal. Its body shape and color pattern are perfectly adapted to the muddy bottom where they inhabit. These fish have a relatively slow growth rate, except during the first year of life when growth is rapid.

Ecology

This species is rather rare, confined to the deeper and slow-moving parts of large rivers together with some "Loricaria" and "Potamotrygon". The position of the eyes and the shape of the mouth of this piscivorous fish indicate its stalking mode of hunting; these fish feed on benthic organisms and other fish. During the receding period, these fish migrate and leave the flooded areas and return to the river channel.

Relationship to humans

The meat of this species is highly valued. This animal is found in the fish market of Cuiabá River in March, April, September, and October. In the southern Pantanal, landing data, including professional and recreational fishing results for 1999, recorded 7.8 metric tons. The accumulated amount of fish landed from 1994 to 1999 was 50 metric tons.

References