Gyrinocheilus aymonieri
Encyclopedia
Gyrinocheilus aymonieri is a freshwater
fish that is native to large parts of southeast Asia. It is of interest as a local food source and for the aquarium trade, being first imported into Germany in 1956.
G. aymonieri is found in the Chao Phraya basin, northern Malay Peninsula
, Mekong
basin (in Cambodia
, Yunnan
province in China, Laos
and Thailand
), Mae Klong
basin and Xe Bang Fai River
. It is most often seen in large rivers, occasionally entering flooded fields. The fish spend most of their time on flat surfaces, such as rocks, in flowing water, using its unusually formed inferior mouth to attach itself to rocks in stronger flows.
The fish are sold in local markets as a food source and small fish are used in preparation of prahok
.
Wild type colour varies from pale grey to olive, with darker markings along the lateral line which vary from a solid stripe with alternating higher and lower extensions to uneven dots. Belly is usually paler than the base colour. Some darker markings may also be observed along the back and on the caudal fin, but there are no dark markings on pelvic and anal fins.
fish. The species rarely reaches its potential length in home aquaria, possibly because it is often kept in aquaria which are too small or in wrong conditions. It is available in a number of colour morphs, including wild type, gold, marble, albino
and lecustic forms.
It is often recommended that the fish is kept in aquaria which are at least 120-150 cm (48-60 inches) long due to its adult size and high level of activity. Faster flows are also advised due to its natural habitat.
The species does not breed readily in home aquaria, although there are occasional reports of fry being found in overgrown aquaria. At this time, there is no definitive knowledge of spawning triggers. Sexing is difficult, although mature males may develop breeding tubercles on their noses, while females become plumper.
G. aymonieri are often bough as algae eaters because they will readily eat algae when young, but with age, their preference changes towards meatier foods, such as generic prepared aquarium foods, frozen crustaceans and small fish. This change is also reflected in behaviour, which becomes aggressive with age, especially so towards others of their own kind and fishes with similar colors. There have been reports in the online aquarium communities that the G. aymonieri will attack, and kill, even larger fish such as cichlid
s. Not through 'fighting' as such, rather it 'sucks on' to the side of larger fish, and keeps sucking until it removes skin, causing infection and often death. Unlike most fish, it does not need to open it's mouth for the intake of water, meaning that it can effectively suck other fish to death.
The two other Gyrinocheilus species, Gyrinocheilus pennocki and the Gyrinocheilus pustulosus, are rarely seen in the aquarium trade.
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 that is native to large parts of southeast Asia. It is of interest as a local food source and for the aquarium trade, being first imported into Germany in 1956.
G. aymonieri is found in the Chao Phraya basin, northern Malay Peninsula
Malay Peninsula
The Malay Peninsula or Thai-Malay Peninsula is a peninsula in Southeast Asia. The land mass runs approximately north-south and, at its terminus, is the southern-most point of the Asian mainland...
, Mekong
Mekong
The Mekong is a river that runs through China, Burma, Laos, Thailand, Cambodia and Vietnam. It is the world's 10th-longest river and the 7th-longest in Asia. Its estimated length is , and it drains an area of , discharging of water annually....
basin (in Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
, Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
province in China, Laos
Laos
Laos Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ Sathalanalat Paxathipatai Paxaxon Lao, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west...
and 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...
), Mae Klong
Mae Klong
The Mae Klong is a river in western Thailand. The river begins at the confluence of the Khwae Noi or Khwae Sai Yok and the Khwae Yai River or Khwae Si Sawat in Kanchanaburi, pass Ratchaburi Province and empties into the Gulf of Thailand in Samut Songkhram....
basin and Xe Bang Fai River
Xe Bang Fai River
The Xe Bang Fai River or Nam Xebangfai is a river of Laos. It flows through Khammouane Province and Savannakhet Province. Nam Theun 2 Dam released water from Nam Theun river into it, thereby increasing its flow and producing hydroelectricity in the process....
. It is most often seen in large rivers, occasionally entering flooded fields. The fish spend most of their time on flat surfaces, such as rocks, in flowing water, using its unusually formed inferior mouth to attach itself to rocks in stronger flows.
The fish are sold in local markets as a food source and small fish are used in preparation of prahok
Prahok
Prahok is a crushed, salted and fermented fish paste that is used in Cambodian cuisine as a seasoning or a condiment. It originated as a way of preserving fish during the longer months when fresh fish was not available in abundant supply...
.
Physical description
G. aymonieri has been recorded as reaching at least 28 cm (11.02 inches) SL and is the only species in the genus to have 9 branched dorsal rays, 36-40 lateral line scales The mouth is inferior with a special "sucker" modification which allows the fish to attach itself to smooth surfaces. No barbels are present.Wild type colour varies from pale grey to olive, with darker markings along the lateral line which vary from a solid stripe with alternating higher and lower extensions to uneven dots. Belly is usually paler than the base colour. Some darker markings may also be observed along the back and on the caudal fin, but there are no dark markings on pelvic and anal fins.
In aquaria
G. aymonieri is similar in colouration to a number of other species which are commonly available in the aquarium trade, such as Crossocheilus oblongus, Epalzeorhynchos kalopterus and Garra cambodgiensis, and is sometimes mis-identified as one of the other species. This leads to some confusion about the reported behaviour of the fish as some of the similar species are peaceful, shoalingShoaling and schooling
In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...
fish. The species rarely reaches its potential length in home aquaria, possibly because it is often kept in aquaria which are too small or in wrong conditions. It is available in a number of colour morphs, including wild type, gold, marble, albino
Albinism
Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of an enzyme involved in the production of melanin...
and lecustic forms.
It is often recommended that the fish is kept in aquaria which are at least 120-150 cm (48-60 inches) long due to its adult size and high level of activity. Faster flows are also advised due to its natural habitat.
The species does not breed readily in home aquaria, although there are occasional reports of fry being found in overgrown aquaria. At this time, there is no definitive knowledge of spawning triggers. Sexing is difficult, although mature males may develop breeding tubercles on their noses, while females become plumper.
G. aymonieri are often bough as algae eaters because they will readily eat algae when young, but with age, their preference changes towards meatier foods, such as generic prepared aquarium foods, frozen crustaceans and small fish. This change is also reflected in behaviour, which becomes aggressive with age, especially so towards others of their own kind and fishes with similar colors. There have been reports in the online aquarium communities that the G. aymonieri will attack, and kill, even larger fish such as cichlid
Cichlid
Cichlids are fishes from the family Cichlidae in the order Perciformes. Cichlids are members of a group known as the Labroidei along with the wrasses , damselfish , and surfperches . This family is both large and diverse. At least 1,300 species have been scientifically described, making it one of...
s. Not through 'fighting' as such, rather it 'sucks on' to the side of larger fish, and keeps sucking until it removes skin, causing infection and often death. Unlike most fish, it does not need to open it's mouth for the intake of water, meaning that it can effectively suck other fish to death.
The two other Gyrinocheilus species, Gyrinocheilus pennocki and the Gyrinocheilus pustulosus, are rarely seen in the aquarium trade.