Anabantoidei
Encyclopedia
The Anabantoidei is a suborder of perciform
ray-finned freshwater
fish
distinguished by their possession of a lung
-like labyrinth organ, which enables them to breathe air. The fish in the Anabantoidei suborder are known as anabantoids or labyrinth fish. Some labyrinth fish are important food fish and many others, such as the Siamese fighting fish
and paradise fish
, are popular as aquarium fish.
ized expansion of the epibranchial bone of the first gill arch and used for respiration
in air.
This organ allows labyrinth fish to take in oxygen
directly from the air, instead of taking it from the water in which they reside through use of gills. The labyrinth organ helps the inhaled oxygen to be absorbed into the bloodstream. As a result, labyrinth fish can survive for a short period of time out of water, as they can inhale the air around them, provided they stay moist.
Labyrinth fish are not born with functional labyrinth organs. The development of the organ is gradual and most labyrinth fish fry
breathe entirely with their gills and develop the labyrinth organs when they grow older.
and Africa
. In Asia, they are found throughout East
, Southeast
, and South Asia
, especially but not exclusively in the warm, slow-flowing, low-oxygen waters. In Africa, significantly smaller numbers of labyrinth fish can be found in the lower half of the continent, with concentrations in the rainforest waters.
The characteristics of the fish habitats are indicators of the size of the labyrinth organ, as the organ size is negatively correlated with the level of oxygen in the waters. Species native to low-oxygen waters are more likely to have larger and more complex labyrinth organs than species found in fast-flowing, oxygen-rich waters.
In general, the labyrinth fish are carnivore
s that eat small aquatic organisms and carrion. Some species will also consume algae and water plants. Most fish are active during daytime but several African species feed at twilight and night. Species of the genus Colisa
can spit water toward insects to bring them down to the water surface, similarly to the archerfish
behavior.
Labyrinth fish are well-known for their bubble nest
ing behavior, although some species do not build bubble nests and employ other methods of brooding. For the bubble nesting species, males establish nesting territories and defend them vigorously. As the name suggests, the bubble nests are floating bubbles coated with oral mucus from the males. Typically, the male bubble nesters stay nearby to guard the nests and constantly retrieve any falling eggs and fry to the nest. Some Betta
species from fast-flowing waters, however, are mouthbrooder
s and do not build bubble nests. In these species, males hold the eggs and fry in their mouth and release the free-swimming fry about a week to ten days after spawning.
Several labyrinth fish are important food sources in their native countries. The giant gourami
in particular, is highly valued as food fish, due to its size and tender flesh with few spines. This species is farmed
extensively in Thailand
and other Southeast Asia
n countries and was intentionally introduced in tropical and subtropical waters around the world. During the colonial period
, the French attempted to introduce this fish to many of their territories. Although an attempt to introduce a population in southern France
failed, the giant gourami became well established in other French colonies. In the late 1880s, there were unsuccessful attempts to introduce the giant gourami to California
waters as food fish. In the 1950s, the giant gourami population was established in Hawaii.
Other smaller labyrinth fish, such as the climbing perch, the kissing gourami
, the snakeskin gourami
, and other gouramies of the genus Trichogaster
are local food fish in Southeast Asia
. In some areas, the fish are processed into salted and dried food.
The Siamese fighting fish
is perhaps the most popular labyrinth fish in the aquarium trade. The paradise fish
also has a long aquarium history and was one of the first aquarium fish introduced to the West. Many species of gourami
es, particular the three spot gourami
and the dwarf gourami
, are commercially bred for the trade and several color morphs are commonly available. Because of their capability to utilize atmospheric oxygen, these fish generally are not so dependent on a form of aeration
in their tank, as they can rise to the surface of the water and take a breath. Unfortunately, because of this quality, labyrinth fish are often kept in small confined areas, or even tiny cups in the case of the Siamese fighting fish
. Many of the labyrinth fish are peaceful and do well in most community tank
s. However, individual males, especially the Siamese fighting fish
and paradise fish
, are territorial towards each other. So, a large aquarium with only one male per tank is ideal to reduce aggression.
Perciformes
The Perciformes, also called the Percomorphi or Acanthopteri, is one of the largest orders of vertebrates, containing about 40% of all bony fish. Perciformes means perch-like. They belong to the class of ray-finned fish and comprise over 7,000 species found in almost all aquatic environments...
ray-finned freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
distinguished by their possession of a lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
-like labyrinth organ, which enables them to breathe air. The fish in the Anabantoidei suborder are known as anabantoids or labyrinth fish. Some labyrinth fish are important food fish and many others, such as the Siamese fighting fish
Siamese fighting fish
The Siamese fighting fish , also known as the betta , is a popular species of freshwater aquarium fish. The name of the genus is derived from ikan bettah, taken from a local dialect of Malay...
and paradise fish
Paradise fish
Paradise fish or paradise gouramis are small freshwater labyrinth fish found in ditches and paddy fields in East Asia, ranging from the Korean Peninsula to Northern Vietnam....
, are popular as aquarium fish.
Labyrinth organ
The labyrinth organ, a defining characteristic of fish in the suborder Anabantoidei, is a much-folded suprabranchial accessory breathing organ. It is formed by vascularBlood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
ized expansion of the epibranchial bone of the first gill arch and used for respiration
Respiration (physiology)
'In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...
in air.
This organ allows labyrinth fish to take in oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
directly from the air, instead of taking it from the water in which they reside through use of gills. The labyrinth organ helps the inhaled oxygen to be absorbed into the bloodstream. As a result, labyrinth fish can survive for a short period of time out of water, as they can inhale the air around them, provided they stay moist.
Labyrinth fish are not born with functional labyrinth organs. The development of the organ is gradual and most labyrinth fish fry
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
breathe entirely with their gills and develop the labyrinth organs when they grow older.
Range
Labyrinth fish are endemic to freshwaters of AsiaAsia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. In Asia, they are found throughout East
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...
, Southeast
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
, and South Asia
South Asia
South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...
, especially but not exclusively in the warm, slow-flowing, low-oxygen waters. In Africa, significantly smaller numbers of labyrinth fish can be found in the lower half of the continent, with concentrations in the rainforest waters.
The characteristics of the fish habitats are indicators of the size of the labyrinth organ, as the organ size is negatively correlated with the level of oxygen in the waters. Species native to low-oxygen waters are more likely to have larger and more complex labyrinth organs than species found in fast-flowing, oxygen-rich waters.
Behavior
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
s that eat small aquatic organisms and carrion. Some species will also consume algae and water plants. Most fish are active during daytime but several African species feed at twilight and night. Species of the genus Colisa
Colisa
Trichogaster is a small genus of tropical or subtropical Asian freshwater labyrinth fish of the gourami family. Species of this genus are popular aquarium fishes...
can spit water toward insects to bring them down to the water surface, similarly to the archerfish
Archerfish
The archerfish are a family of fish known for their habit of preying on land based insects and other small animals by literally shooting them down with water droplets from their specialized mouths...
behavior.
Labyrinth fish are well-known for their bubble nest
Bubble nest
Bubblenests, also spelled bubble nests or bubble-nests, created by some fish species, are floating masses of bubbles blown with an oral secretion, saliva bubbles, and occasionally aquatic plants, or an area for egg deposit attached at the bottom. Fish that build and guard bubble nests are known as...
ing behavior, although some species do not build bubble nests and employ other methods of brooding. For the bubble nesting species, males establish nesting territories and defend them vigorously. As the name suggests, the bubble nests are floating bubbles coated with oral mucus from the males. Typically, the male bubble nesters stay nearby to guard the nests and constantly retrieve any falling eggs and fry to the nest. Some Betta
Betta
Betta is a large genus of small, often colorful, freshwater ray-finned fishes in the gourami family . The type species is B. picta, the spotted betta.By far the best known Betta species, however, is B...
species from fast-flowing waters, however, are mouthbrooder
Mouthbrooder
Mouthbrooding, also known as oral incubation and buccal incubation, is the care given by some groups of animals to their offspring by holding them in the mouth of the parent for extended periods of time. Although mouthbrooding is performed by a variety of different animals, most notably Darwin's...
s and do not build bubble nests. In these species, males hold the eggs and fry in their mouth and release the free-swimming fry about a week to ten days after spawning.
Anabantoids as food fish
Giant gourami
The Giant Gourami is a gourami, a freshwater fish belonging to the sub-family Osphroneminae in the family Osphronemidae. Some other larger members of this family are also occasionally or regionally referred to as "giant gouramis", including the banded gourami, Trichogaster fasciatus, and the three...
in particular, is highly valued as food fish, due to its size and tender flesh with few spines. This species is farmed
Fish farming
Fish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases young fish into the wild for recreational fishing or to supplement a species'...
extensively in Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
and other Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
n countries and was intentionally introduced in tropical and subtropical waters around the world. During the colonial period
Colonial Period
Colonial Period may generally refer to any period in a country's history when it was subject to administration by a colonial power.*Korea under Japanese rule*Colonial history of the United States...
, the French attempted to introduce this fish to many of their territories. Although an attempt to introduce a population in southern France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
failed, the giant gourami became well established in other French colonies. In the late 1880s, there were unsuccessful attempts to introduce the giant gourami to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
waters as food fish. In the 1950s, the giant gourami population was established in Hawaii.
Other smaller labyrinth fish, such as the climbing perch, the kissing gourami
Kissing gourami
Kissing gouramis, also known as kissing fish or kissers , are large tropical freshwater fish comprising the monotypic labyrinth fish family Helostomatidae . These fish originate from Thailand to Indonesia. They can befood fish which are farmed in their native Southeast Asia...
, the snakeskin gourami
Snakeskin gourami
Trichopodus pectoralis, also known as snakeskin gourami and Siamese gourami is a species of gourami that is important both as a food fish and as an aquarium fish.-Physical characteristics:...
, and other gouramies of the genus Trichogaster
Trichogaster
Trichopodus is a genus of tropical freshwater labyrinth fish of the gourami family found in Southeast Asia. Gouramis of the Trichopodus genus are closely related to those of Trichogaster , species of both genera have long, thread-like pelvic fins used to sense the environment...
are local food fish in Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
. In some areas, the fish are processed into salted and dried food.
Anabantoids as aquarium fish
Siamese fighting fish
The Siamese fighting fish , also known as the betta , is a popular species of freshwater aquarium fish. The name of the genus is derived from ikan bettah, taken from a local dialect of Malay...
is perhaps the most popular labyrinth fish in the aquarium trade. The paradise fish
Paradise fish
Paradise fish or paradise gouramis are small freshwater labyrinth fish found in ditches and paddy fields in East Asia, ranging from the Korean Peninsula to Northern Vietnam....
also has a long aquarium history and was one of the first aquarium fish introduced to the West. Many species of gourami
Gourami
Gouramis are a family, Osphronemidae, of freshwater perciform fishes. The fish are native to Asia, from Pakistan and India to the Malay Archipelago and north-easterly towards Korea. The name "gourami" is also used for fish of the families Helostomatidae and Anabantidae. "Gouramis" is an example of...
es, particular the three spot gourami
Three spot gourami
The three spot gourami, Trichopodus trichopterus, is a labyrinth fish. The natural coloration of this fish gets its name from the two spots along each side of its body in line with the eye, considered the third spot. Marketed fresh or salted and pickled, they are also popular in the fishkeeping...
and the dwarf gourami
Dwarf gourami
The dwarf gourami, Trichogaster lalius , has an almost translucent blue color, with vertical red to dark orange stripes. In its native range it is dried for food, and it is also kept as an aquarium fish. It has become highly popular for aquaria.Dwarf gouramis from Singapore may carry dwarf gourami...
, are commercially bred for the trade and several color morphs are commonly available. Because of their capability to utilize atmospheric oxygen, these fish generally are not so dependent on a form of aeration
Aeration
Aeration is the process by which air is circulated through, mixed with or dissolved in a liquid or substance.-Aeration of liquids:-Methods:Aeration of liquids is achieved by:...
in their tank, as they can rise to the surface of the water and take a breath. Unfortunately, because of this quality, labyrinth fish are often kept in small confined areas, or even tiny cups in the case of the Siamese fighting fish
Siamese fighting fish
The Siamese fighting fish , also known as the betta , is a popular species of freshwater aquarium fish. The name of the genus is derived from ikan bettah, taken from a local dialect of Malay...
. Many of the labyrinth fish are peaceful and do well in most community tank
Community tank
Community aquaria are tanks that are designed to contain more than one species of fish. Most commonly they include a variety of species that do not normally occur together in nature, for example angelfish from Brazil, swordtails from Mexico, and gouramis from South East Asia...
s. However, individual males, especially the Siamese fighting fish
Siamese fighting fish
The Siamese fighting fish , also known as the betta , is a popular species of freshwater aquarium fish. The name of the genus is derived from ikan bettah, taken from a local dialect of Malay...
and paradise fish
Paradise fish
Paradise fish or paradise gouramis are small freshwater labyrinth fish found in ditches and paddy fields in East Asia, ranging from the Korean Peninsula to Northern Vietnam....
, are territorial towards each other. So, a large aquarium with only one male per tank is ideal to reduce aggression.