Brachyplatystoma
Encyclopedia
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 3.6 metres (11.8 ft) in length. Brachyplatystoma are found in the Amazon
and Orinoco Rivers, and other tropical freshwater and brackish habitats in South America
. Some species are migratory
. These fish are important as food fish
and, to some extent, aquarium
fish.
brachys, platys, and stoma, which mean short, flat, and mouth respectively. This genus was erected in 1862 by Pieter Bleeker
. The type species is B. vaillantii. The subgenus Malacobagrus is applied to B. capapretum, B. filamentosum, B. rousseauxii, and the extinct species B. promagdalena, which only is known from fossil
remains.
Brachyplatystoma and its monotypic
sister group Platynematichthys are the only genera in the tribe Brachyplatystomatini. These two genera are characterized by two synapomorphies; these include a gas bladder
divided into an anterior
portion and a triangular posterior
portion, as well as a ventral
crest under the cleithrum
, the main bone supporting the pectoral fins.
The genus Brachyplatystoma was previously not monophyletic
; to correct this, the genera Merodontotus and Goslinia are now both included under Brachyplatysoma. Furthermore, a new species was described in 2005, which brings the species count to seven extant species. B. capapretum is sister to B. filamentosum.
B. flavicans is not actually a species of Brachyplatystoma; this name is a commonly used synonym of Zungaro zungaro
.
s that extend past the dorsal fin
in all species, but may even extend to the caudal fin. The caudal fin of adult Brachyplatystoma fish is moderately to deeply forked. Brachyplatystoma have specialized pelagic young with greatly elongated barbels and fin filaments, and strongly ornamented pectoral spines.
This genus is characterized by two synapomorphies
. One of these is modified jaw muscles. The other, more obvious trait, is only found in juveniles and subadults, in which the upper and lower rays of the caudal fin are extended into long filaments. B. vaillantii is the sister species to all other Brachyplatystoma, marked by differences in the skull
, jaw
, and other bones. The subgenus Malacobagrus is characterized by their derived lateral line
, Weberian apparatus
, a subquadrangular gill cover
(as opposed to triangular in other species), and pectoral spine.
As mentioned, one of the characteristics of this genus is caudal fin filaments on younger fish. In most of the species these filaments are lost in adulthood, though they are retained in B. tigrinum, B. juruense, and B. platynemum. Many Brachyplatystoma exhibit countershading
, in which the dorsal
surface is darker, and then fades to a lighter belly. In most species, this is consistent throughout life, though there are some exceptions. Juvenile B. capapretum and B. filamentosum exhibit dorsal and lateral spots which mostly disappear in the adult form. Juvenile B. juruense and B. tigrinum exhibit lateral spots that expand to form vertical stripes as the fish matures.
B. capapretum, described in 2005, was previously misidentified as B. filamentosum. These two species are closely related. However, these species differ in premaxillary dentition, juvenile and adult coloration, and adult maxillary barbel length and caudal fin shape. These two species exhibit spotted juvenile stages, though in B. capapretum these spots are much larger than the eye, while in B. filamentosum these spots are about the same size as the eye. Also, the cross section
of the caudal peduncle
is rounded in these two species, as opposed to a deeper, thinner cross section in other Brachyplatystoma species. The adult B. capapretum has a very dark or even black dorsum (its species name is derived from Portuguese
which means black cape), as opposed to the lighter dorsal surface of B. filamentosum.
Brachyplatystoma includes some of the largest species of Amazon
ian catfish, including the Piraíba, B. filamentosum, which reaches about 3.6 metres (11.8 ft) in length and weigh about 200 kilograms (440.9 lb). Even the most modest species reach about 60 centimetres (23.6 in). The other species range in size from about 1–2 m (3.3–6.6 ft).
B. filamentosum and B. rousseauxii have a mysterious "milk
" gland
at the anterior upper part of its pectoral fins. Its function is unknown, but in Colombia
this fish is known as lechero, which means milkman.
The world record recognized by IGFA for the Brachyplatystoma filamentosum, belongs to the Brazilian Jorge Masullo de Aguiar with 155 Kg.
, Orinoco, and The Guyanas in South America
. The genus does not occur west or north of the Andes
or in the Venezuelan Coastal Range
. These fish generally inhabit areas that have a soft substrate, such as mud or sand. The fossil catfish B. promagdalena has been found in Colombia
in an area now drained by the Magdalena River
, where Brachyplatystoma species are currently absent; during the Miocene
, this area had been drained by the Amazon and Orinoco system.
. However, stomach contents of B. filamentosum has been shown to contain monkey
s.
Some of the species of Brachyplatystoma migrate long distances for reproduction. This is known in B. vaillantii, B. platynemum, and B. rousseauxii, but data about the migratory habits of other species are scant. This migration is associated with white water rivers, as black water
does not contain enough food for migrating Pimelodids. Maturation
is timed to the increase in river level. Migration begins as the river level begins to rise with the coming of the rainy season. B. rousseauxii has the longest reproductive migration of any freshwater fish; from the mouth of the Amazon
, migration may stretch 5500 kilometres (3,417.6 mi), a trip which may last five to six months, before they spawn in the western tributaries of the Amazon. It is hypothesized that B. rousseauxii is homing, that is, it will return to the tributary to which it was born in. Before spawning, the stomach
s of these fish are empty due to high digestive efficiency.
The young are carried downstream until they reach estuaries
. Juveniles and subadults are commonly found in these habitats. They may even live in brackish waters at this time. They will live in these estuaries and river mouths for about three years here before entering the lower reaches of the river. At this still immature stage, they may form groups or school. This is the first record of young, migratory fish in the Amazon basin.
, thousands of metric tons of fish from this genus are caught for both local consumption as well as exportation. These fish are usually caught with the use of longline
s or drift net
s. They are also captured by harpoon
as well as rope
s with large fish hook
s at the end. B. filamentosum is a major fishery, and B. rousseauxii has become the most important species in the Amazon River basin. B. rousseauxii and B. vaillantii constitute a significant percentage of Amazonian food fish. The flesh of many of these fish is considered to be of excellent quality.
Human activities are a concern in that they may disrupt these fishes. Dams may impede the migration of these fish both to and from their spawning sites. Gold prospecting
may also frighten these large catfishes in the areas where they spawn. Deforestation can also affect the upriver spawning habitats. Because these fish may migrate back to their original tributary, overfishing in a certain area may reduce a whole genetic group. In some areas, catches have been diminishing due to overfishing
. B. rousseauxii is known to be overfished, and this same situation may apply to other Brachyplatystoma. Catch rates of B. filamentosum have decreased drastically from 1977.
trade. The large size of many of these fish prohibit them from being maintained in anything but the largest of aquaria
, or in public aquariums. B. tigrinum is a highly-prized fish in the fishkeeping
hobby, and is one of the most expensive fish in this family.
These fish should be kept in well-oxygenated aquarium with a high current. Due to their large size, the aquarium should also be spacious and any tankmates must be large enough not to be eaten. The aquarium should not be brightly lit, and hiding places should be available. Breeding is unreported in captivity. Due to the similarity between B. tigrinum and B. juruense, the latter is often known as the False Zebra Shovelnose or False Tigrinus (as B. tigrinum was previously known as Merodontotus tigrinus).
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...
of 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...
from the family 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...
. 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 3.6 metres (11.8 ft) in length. Brachyplatystoma are found in 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...
and Orinoco Rivers, and other tropical freshwater and brackish habitats in South America
South 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...
. Some species are migratory
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...
. These fish are important as food fish
Fish (food)
Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history.-Terminology:...
and, to some extent, aquarium
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
fish.
Taxonomy
Brachyplatystoma originates from GreekGreek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
brachys, platys, and stoma, which mean short, flat, and mouth respectively. This genus was erected in 1862 by Pieter Bleeker
Pieter Bleeker
Pieter Bleeker was a Dutch medical doctor and ichthyologist, famous for his work on the fishes of East Asia – Atlas Ichthyologique des Orientales Neerlandaises – which was published 1862–1877....
. The type species is B. vaillantii. The subgenus Malacobagrus is applied to B. capapretum, B. filamentosum, B. rousseauxii, and the extinct species B. promagdalena, which only is known from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
remains.
Brachyplatystoma and its monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
sister group Platynematichthys are the only genera in the tribe Brachyplatystomatini. These two genera are characterized by two synapomorphies; these include a gas bladder
Gas bladder
The swim bladder, gas bladder, fish maw or air bladder is an internal gas-filled organ that contributes to the ability of a fish to control its buoyancy, and thus to stay at the current water depth without having to waste energy in swimming...
divided into an anterior
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
portion and a triangular posterior
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
portion, as well as a ventral
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
crest under the cleithrum
Cleithrum
The cleithrum is a membrane bone which first appears as part of the skeleton in primitive bony fish, where it runs vertically along the scapula. Its name is derived from Greek κλειθρον = "key ", by analogy with "clavicle" from Latin clavicula = "little key".In modern fishes, the cleithrum is a...
, the main bone supporting the pectoral fins.
The genus Brachyplatystoma was previously not 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...
; to correct this, the genera Merodontotus and Goslinia are now both included under Brachyplatysoma. Furthermore, a new species was described in 2005, which brings the species count to seven extant species. B. capapretum is sister to B. filamentosum.
B. flavicans is not actually a species of Brachyplatystoma; this name is a commonly used synonym of Zungaro zungaro
Zungaro zungaro
The Jau is a South American catfish of the family Pimelodidae.-Taxonomy:By some sources, it is the only species of the monotypic genus Zungaro. However, some sources list other species as valid, such as Zungaro jahu. This species may be referred to by one of its synonyms, Brachyplatystoma flavicans...
.
Anatomy and appearance
Brachyplatystoma all exhibit long maxillary barbelBarbel (anatomy)
A barbel on a fish is a slender, whiskerlike tactile organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, sturgeon, the zebrafish and some species of shark...
s that extend past the dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
in all species, but may even extend to the caudal fin. The caudal fin of adult Brachyplatystoma fish is moderately to deeply forked. Brachyplatystoma have specialized pelagic young with greatly elongated barbels and fin filaments, and strongly ornamented pectoral spines.
This genus is characterized by two synapomorphies
Synapomorphy
In cladistics, a synapomorphy or synapomorphic character is a trait that is shared by two or more taxa and their most recent common ancestor, whose ancestor in turn does not possess the trait. A synapomorphy is thus an apomorphy visible in multiple taxa, where the trait in question originates in...
. One of these is modified jaw muscles. The other, more obvious trait, is only found in juveniles and subadults, in which the upper and lower rays of the caudal fin are extended into long filaments. B. vaillantii is the sister species to all other Brachyplatystoma, marked by differences in the skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...
, jaw
Jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...
, and other bones. The subgenus Malacobagrus is characterized by their derived lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
, Weberian apparatus
Ostariophysi
Ostariophysi is the second-largest superorder of fish. Members of this superorder are called ostariophysians. This diverse group contains almost 8,000 species, about 28% of known fish species in the world and 68% of freshwater species, and are present on all major continents except Antarctica...
, a subquadrangular gill cover
Operculum (fish)
The operculum of a bony fish is the hard bony flap covering and protecting the gills. In most fish, the rear edge of the operculum roughly marks the division between the head and the body....
(as opposed to triangular in other species), and pectoral spine.
As mentioned, one of the characteristics of this genus is caudal fin filaments on younger fish. In most of the species these filaments are lost in adulthood, though they are retained in B. tigrinum, B. juruense, and B. platynemum. Many Brachyplatystoma exhibit countershading
Countershading
Countershading, or Thayer's Law, is a form of camouflage. Countershading, in which an animal’s pigmentation is darker dorsally, is often thought to have an adaptive effect of reducing conspicuous shadows cast on the ventral region of an animal’s body...
, in which the dorsal
Anatomical terms of location
Standard anatomical terms of location are designations employed in science that deal with the anatomy of animals to avoid ambiguities that might otherwise arise. They are not language-specific, and thus require no translation...
surface is darker, and then fades to a lighter belly. In most species, this is consistent throughout life, though there are some exceptions. Juvenile B. capapretum and B. filamentosum exhibit dorsal and lateral spots which mostly disappear in the adult form. Juvenile B. juruense and B. tigrinum exhibit lateral spots that expand to form vertical stripes as the fish matures.
B. capapretum, described in 2005, was previously misidentified as B. filamentosum. These two species are closely related. However, these species differ in premaxillary dentition, juvenile and adult coloration, and adult maxillary barbel length and caudal fin shape. These two species exhibit spotted juvenile stages, though in B. capapretum these spots are much larger than the eye, while in B. filamentosum these spots are about the same size as the eye. Also, the cross section
Cross section (geometry)
In geometry, a cross-section is the intersection of a figure in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc...
of the caudal peduncle
Fish anatomy
Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does.- Body :...
is rounded in these two species, as opposed to a deeper, thinner cross section in other Brachyplatystoma species. The adult B. capapretum has a very dark or even black dorsum (its species name is derived from Portuguese
Portuguese language
Portuguese is a Romance language that arose in the medieval Kingdom of Galicia, nowadays Galicia and Northern Portugal. The southern part of the Kingdom of Galicia became independent as the County of Portugal in 1095...
which means black cape), as opposed to the lighter dorsal surface of B. filamentosum.
Brachyplatystoma includes some of the largest species of 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...
ian catfish, including the Piraíba, B. filamentosum, which reaches about 3.6 metres (11.8 ft) in length and weigh about 200 kilograms (440.9 lb). Even the most modest species reach about 60 centimetres (23.6 in). The other species range in size from about 1–2 m (3.3–6.6 ft).
B. filamentosum and B. rousseauxii have a mysterious "milk
Milk
Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...
" gland
Gland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...
at the anterior upper part of its pectoral fins. Its function is unknown, but in Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
this fish is known as lechero, which means milkman.
The world record recognized by IGFA for the Brachyplatystoma filamentosum, belongs to the Brazilian Jorge Masullo de Aguiar with 155 Kg.
Distribution and habitat
Fish of this genus are found in the AmazonAmazon 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...
, Orinoco, and The Guyanas in South America
South 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...
. The genus does not occur west or north of the Andes
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
or in the Venezuelan Coastal Range
Venezuelan Coastal Range
The Venezuelan Coastal Range is a mountain range that runs along the central and eastern portions of Venezuela's northern coast...
. These fish generally inhabit areas that have a soft substrate, such as mud or sand. The fossil catfish B. promagdalena has been found in Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
in an area now drained by the Magdalena River
Magdalena River
The Magdalena River is the principal river of Colombia, flowing northward about through the western half of the country. It takes its name from the biblical figure Mary Magdalene. It is navigable through much of its lower reaches, in spite of the shifting sand bars at the mouth of its delta, as...
, where Brachyplatystoma species are currently absent; during the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
, this area had been drained by the Amazon and Orinoco system.
Ecology
These fish are mainly piscivorousPiscivore
A piscivore is a carnivorous animal which eats primarily fish. Piscivory was the diet of early tetrapods , insectivory came next, then in time reptiles added herbivory....
. However, stomach contents of B. filamentosum has been shown to contain monkey
Monkey
A monkey is a primate, either an Old World monkey or a New World monkey. There are about 260 known living species of monkey. Many are arboreal, although there are species that live primarily on the ground, such as baboons. Monkeys are generally considered to be intelligent. Unlike apes, monkeys...
s.
Some of the species of Brachyplatystoma migrate long distances for reproduction. This is known in B. vaillantii, B. platynemum, and B. rousseauxii, but data about the migratory habits of other species are scant. This migration is associated with white water rivers, as black water
Blackwater river
A blackwater river is a river with a deep, slow-moving channel that flows through forested swamps and wetlands. As vegetation decays in the water, tannins are leached out, resulting in transparent, acidic water that is darkly stained, resembling tea or coffee. Most major blackwater rivers are in...
does not contain enough food for migrating Pimelodids. Maturation
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
is timed to the increase in river level. Migration begins as the river level begins to rise with the coming of the rainy season. B. rousseauxii has the longest reproductive migration of any freshwater fish; from the mouth of 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...
, migration may stretch 5500 kilometres (3,417.6 mi), a trip which may last five to six months, before they spawn in the western tributaries of the Amazon. It is hypothesized that B. rousseauxii is homing, that is, it will return to the tributary to which it was born in. Before spawning, the stomach
Stomach
The stomach is a muscular, hollow, dilated part of the alimentary canal which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects , and molluscs. It is involved in the second phase of digestion, following mastication .The stomach is...
s of these fish are empty due to high digestive efficiency.
The young are carried downstream until they reach estuaries
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
. Juveniles and subadults are commonly found in these habitats. They may even live in brackish waters at this time. They will live in these estuaries and river mouths for about three years here before entering the lower reaches of the river. At this still immature stage, they may form groups or school. This is the first record of young, migratory fish in the Amazon basin.
Relationship to humans
Brachyplatystoma are important food fish. In the Amazon BasinAmazon Basin
The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...
, thousands of metric tons of fish from this genus are caught for both local consumption as well as exportation. These fish are usually caught with the use of longline
Long-line fishing
Longline fishing is a commercial fishing technique. It uses a long line, called the main line, with baited hooks attached at intervals by means of branch lines called "snoods". A snood is a short length of line, attached to the main line using a clip or swivel, with the hook at the other end....
s or drift net
Drift net
Drift netting is a fishing technique where nets, called drift nets, are allowed to float freely at the surface of a sea or lake. Usually a drift net is a gill net with floats attached to a rope along the top of the net, and weights attached to another rope along the foot of the net to keep the net...
s. They are also captured by harpoon
Harpoon
A harpoon is a long spear-like instrument used in fishing to catch fish or large marine mammals such as whales. It accomplishes this task by impaling the target animal, allowing the fishermen to use a rope or chain attached to the butt of the projectile to catch the animal...
as well as rope
Rope
A rope is a length of fibres, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength...
s with large fish hook
Fish hook
A fish hook is a device for catching fish either by impaling them in the mouth or, more rarely, by snagging the body of the fish. Fish hooks have been employed for centuries by fishermen to catch fresh and saltwater fish. In 2005, the fish hook was chosen by Forbes as one of the top twenty tools...
s at the end. B. filamentosum is a major fishery, and B. rousseauxii has become the most important species in the Amazon River basin. B. rousseauxii and B. vaillantii constitute a significant percentage of Amazonian food fish. The flesh of many of these fish is considered to be of excellent quality.
Human activities are a concern in that they may disrupt these fishes. Dams may impede the migration of these fish both to and from their spawning sites. Gold prospecting
Gold prospecting
Gold prospecting is the act of searching for new gold deposits. Methods used vary with the type of deposit sought and the resources of the prospector...
may also frighten these large catfishes in the areas where they spawn. Deforestation can also affect the upriver spawning habitats. Because these fish may migrate back to their original tributary, overfishing in a certain area may reduce a whole genetic group. In some areas, catches have been diminishing due to overfishing
Overfishing
Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans....
. B. rousseauxii is known to be overfished, and this same situation may apply to other Brachyplatystoma. Catch rates of B. filamentosum have decreased drastically from 1977.
In the aquarium
Brachyplatystoma are generally uncommon in the fishkeepingFishkeeping
Fishkeeping is a popular hobby concerned with keeping fish in a home aquarium or garden pond. There is also a fishkeeping industry, as a branch of agriculture.-Types of fishkeeping systems:...
trade. The large size of many of these fish prohibit them from being maintained in anything but the largest of aquaria
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
, or in public aquariums. B. tigrinum is a highly-prized fish in the fishkeeping
Fishkeeping
Fishkeeping is a popular hobby concerned with keeping fish in a home aquarium or garden pond. There is also a fishkeeping industry, as a branch of agriculture.-Types of fishkeeping systems:...
hobby, and is one of the most expensive fish in this family.
These fish should be kept in well-oxygenated aquarium with a high current. Due to their large size, the aquarium should also be spacious and any tankmates must be large enough not to be eaten. The aquarium should not be brightly lit, and hiding places should be available. Breeding is unreported in captivity. Due to the similarity between B. tigrinum and B. juruense, the latter is often known as the False Zebra Shovelnose or False Tigrinus (as B. tigrinum was previously known as Merodontotus tigrinus).
Species
The 8 species in the genus Brachyplatystoma have been divided into two subgenera:- Subgenus Brachyplatystoma:
- Brachyplatystoma juruense (BoulengerGeorge Albert BoulengerGeorge Albert Boulenger FRS was a Belgian-British zoologist who identified over 2000 new animal species, chiefly fish, reptiles and amphibians.-Life:...
, 1898) –Zebra catfish, Juruense catfish, Gold Zebra Pim, False Tigrinus. - Brachyplatystoma platynemum Boulenger, 1898 – Slobbering catfish.
- Brachyplatystoma tigrinum (Britski, 1981) – Tigerstriped catfish, Zebra shovelnose, Royal tiger shovelnose.
- Brachyplatystoma vaillantii (ValenciennesAchille ValenciennesAchille Valenciennes was a French zoologist.Valenciennes was born in Paris, and studied under Georges Cuvier. Valenciennes' study of parasitic worms in humans made an important contribution to the study of parasitology...
, 1840) – Laulao catfish, Piramutaba.
- Brachyplatystoma juruense (Boulenger
- Subgenus Malacobagrus
- Brachyplatystoma capapretum Lundberg & Akama, 2005
- Brachyplatystoma filamentosum (Lichtenstein, 1819) – Kumakuma, Piraíba, Filhote.
- †Brachyplatystoma promagdalena Lundberg, 2005 – only known from fossils of MioceneMioceneThe Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
origin. - Brachyplatystoma rousseauxii (CastelnauFrançois Louis de la Porte, comte de CastelnauFrançois Louis Nompar de Caumont LaPorte, comte de Castelnau was a French naturalist, known also as François Laporte or Francis de Castelnau.-Life:Born in London, he studied natural history in Paris...
, 1855) – Dourada (litt. golden in PortuguesePortuguese languagePortuguese is a Romance language that arose in the medieval Kingdom of Galicia, nowadays Galicia and Northern Portugal. The southern part of the Kingdom of Galicia became independent as the County of Portugal in 1095...
. A name also used for several other unrelated species, e.g. Sparus aurata).
External links
- Richter, Enrico: Groß - größer - am größten: Raubwelse der Gattung Brachyplatystoma