Porthole shovelnose catfish
Encyclopedia
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
.
, Pseudoplatystoma
, and Brachyplatystoma
. This genus forms a monophyletic
group with Sorubim
, Sorubimichthys, Pseudoplatystoma
, and Zungaro. Of these genera, Hemisorubim is most closely related to Pseudoplatystoma.
and originates from the Amazon
, Maroni
, Orinoco, and Paraná River
basins. It also occurs in the Pantanal
.
s (20in
) SL
and up to 1,470 gram
s (3.23 lb
). 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.
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.
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.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Hemisorubim of the catfish
Catfish
Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...
(order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Siluriformes) family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Pimelodidae
Pimelodidae
Pimelodidae, commonly known as the long-whiskered catfishes, is a family of catfishes .-Taxonomy:Pimelodidae has undergone much revision. Currently, the family contains about 30 genera and about 90 recognized and known but unnamed species...
.
Taxonomy
This fish is considered one of the "sorubimine" catfishes, an informal group of catfish that includes genera such as SorubimSorubim
Sorubim is a small genus of Pimelodid catfish originating from tropical South America. A number of characteristics allows the differentiation of each species in the genus...
, Pseudoplatystoma
Pseudoplatystoma
Pseudoplatystoma is a genus of several South American catfish species of family Pimelodidae. The three species are known by a number of different common names. They inhabit the major rivers of north-eastern Argentina, Paraguay, Peru, Bolivia, Uruguay and Brazil. They prefer the main channels and...
, and Brachyplatystoma
Brachyplatystoma
Brachyplatystoma is a genus of catfish from the family Pimelodidae. As the occasionally used common name goliath catfishes indicates, this genus includes some of the largest species of catfish, including the Piraíba, B. filamentosum, which reaches about in length...
. This genus forms a monophyletic
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
group with Sorubim
Sorubim
Sorubim is a small genus of Pimelodid catfish originating from tropical South America. A number of characteristics allows the differentiation of each species in the genus...
, Sorubimichthys, Pseudoplatystoma
Pseudoplatystoma
Pseudoplatystoma is a genus of several South American catfish species of family Pimelodidae. The three species are known by a number of different common names. They inhabit the major rivers of north-eastern Argentina, Paraguay, Peru, Bolivia, Uruguay and Brazil. They prefer the main channels and...
, and Zungaro. Of these genera, Hemisorubim is most closely related to Pseudoplatystoma.
Distribution
This species is native to South AmericaSouth America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
and originates from the Amazon
Amazon River
The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...
, Maroni
Maroni River
The Maroni or Marowijne is a river in South America. It originates in the Tumuk Humak Mountains and forms the border between French Guiana and Suriname...
, Orinoco, and Paraná River
Paraná River
The Paraná River is a river in south Central South America, running through Brazil, Paraguay and Argentina for some . It is second in length only to the Amazon River among South American rivers. The name Paraná is an abbreviation of the phrase "para rehe onáva", which comes from the Tupi language...
basins. It also occurs in the Pantanal
Pantanal
The Pantanal is a tropical wetland and one of the world's largest wetland of any kind. Most of it lies within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay, sprawling over an area estimated at between and...
.
Appearance and anatomy
This fish reaches a length of 53 centimetreCentimetre
A centimetre is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of . Hence a centimetre can be written as or — meaning or respectively...
s (20in
Inch
An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...
) SL
Fish measurement
Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...
and up to 1,470 gram
Gram
The gram is a metric system unit of mass....
s (3.23 lb
Pound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...
). 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 LoricariaLoricaria
Loricaria is a genus of catfishes of the family Loricariidae.-Taxonomy:Loricaria was the first genus of the family Loricariidae described. Thus, it is the nominal genus of the family Loricariidae. Phylogenetic relationships within Loricaria and among other members of Loricariini remain uncertain...
and Potamotrygon
Potamotrygon
Potamotrygon is a genus of freshwater stingrays native to the rivers of South America. As of July 2006, FishBase lists seventeen distinct species. The type species is P. hystrix....
. 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
Benthic zone
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many such...
organisms and other fish. During the receding period, these fish migrate
Fish migration
Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres...
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 RiverCuiabá River
The Cuiabá River is a Brazilian river in the southern state of Mato Grosso that flows in the Rio de la Plata Basin....
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.