Scientific classificationedit :
Kingdom:
Animalia
Phylum:
Chordata
Class:
Actinopterygii
Order:
Osteoglossiformes
Family:
Osteoglossidae
Genus:
Scleropages
Species:
S. formosus.
Evolution and taxonomy ;
leichardti, about 140 million years ago, during the Early Cretaceous period. formosus.[12][13]. The morphological similarity of all Scleropages species shows little evolutionary change has taken place recently for these ancient fish.[10][11]
The first description of this species was published in 1840 by German naturalists Salomon Müller and Hermann Schlegel, under the name Osteoglossum formosum, although later this species was placed in Scleropages with the name S. Therefore, their spread throughout the islands of southeast Asia suggests they diverged from other osteoglossids before the continental breakup was complete. Like all members of the Osteoglossidae, Asian arowanas are highly adapted to fresh water and are incapable of surviving in the ocean. jardinii and S. Genetic studies have confirmed this hypothesis, showing the ancestor of the Asian arowanas diverged from the ancestor of the Australian arowanas, S. This divergence took place in the eastern margin of Gondwanaland, with the ancestors of Asian arowanas carried on the Indian subcontinent or smaller landmasses into Asia.
Several distinct, naturally occurring colour varieties are recognised as haplotypes, each found in a specific geographic region. This classification was based on both morphometrics and a phylogenetic analysis using the cytochrome b gene, and includes these species:
Scleropages formosus was redescribed to include the strain known as the green arowana. aureus.
Scleropages macrocephalus described the silver Asian arowana.
Scleropages aureus described the red-tailed golden arowana.
Scleropages legendrei described the super red arowana.
The majority of researchers dispute this reclassification, arguing that the published data are insufficient to justify recognizing more than one Southeast Asian species of Scleropages, and that divergent haplotypes used to distinguish the color strains into isolated species were found within a single color strain, contradicting the findings. They are considered monotypic, consisting of closely related haplotypes.[3][4][5][6][7]. The gold crossback, which was not part of the study, was included in this species by default, though it was suspected to be closely related to S. formosus into four separate species. They include:
The green is the most common variety, found in Indonesia (Kalimantan and Sumatra), Vietnam, Myanmar, Thailand, Cambodia, and Malaysia.
The silver Asian (not to be confused with the silver arowana, Osteoglossum bicirrhosum) is considered part of the green variety by some. It has two subvarieties, the "grey tail silver" or "Pinoh arowana," and the "yellow tail silver," each found in a different part of the island of Borneo.
The red-tailed golden is found in northern Sumatra, Indonesia.
The gold crossback, blue Malayan, or Bukit Merah blue is native to the state of Pahang and the Bukit Merah area in Perak, Peninsular Malaysia.
The red, super red, blood red, or chili red is known only from the upper part of the Kapuas River and nearby lakes in western Indonesian part of Borneo.
In 2003, a study[8] proposed breaking S.
Reproduction :
Both the fertilized eggs and larvae are brooded within the male's mouth.[5][18]. Unlike most fish, the Asian arowana reaches sexual maturity relatively late, after 3–4 yr. After the eggs are fertilized, the Asian arowana exhibits great parental care with paternal mouthbrooding. The females produce few eggs, 30-100, which are quite large.
Behavior ;
They spend the day in the protection of Pandanus roots or other structures, and feed at night.[18].
Relationship with humans :
Its popularity has soared since the late 1970s, and hobbyists may pay thousands of U.S. One belief is that while water is a place where chi gathers, it is naturally a source of yin energy and must contain an "auspicious" fish such as an arowana to have balancing yang energy.[17] Another is that a fish can preserve its owner from death by dying itself.[20]
Conservationv;
Asian arowanas are listed as endangered by the 2006 IUCN Red List, with the most recent evaluation taking place in 1996.[21] International trade in these fishes is controlled under the Convention on the International Trade in Endangered Species of Wild Flora and Fauna (CITES), under which it was placed on Appendix I, the most restrictive category, in 1975.[22] S. dollars for one of these animals.[14][25] Certain color varieties are more endangered than others, since the red and gold varieties are both less common, and in higher demand in the aquarium trade.[7]. Asian arowanas are considered to be symbols of good luck and prosperity, especially by those from Asian cultures. However, habitat loss is likely a greater threat than aquarium collecting.[14]
No recent evaluation of conservation status has been done by the IUCN.[21] Additionally, considering the current confusion as to number of species, as well as the wide distribution, conservation status should be reconsidered. For example, Asian arowanas are now uncommon in the Malay Peninsula, where they were once widely distributed, due to environmental destruction.[14] Inclusion in the IUCN Red List was originally based not on biological reasons but on practical ones: though widely distributed throughout southeast Asia, they have been harvested heavily by aquarium collectors. formosus is one of only eight fish species listed on Appendix I.[23] A number of registered CITES breeders are in Asia, and the specimens they produce can be imported into several nations. This reputation derives from the species' resemblance to the Chinese dragon, considered an auspicious symbol.[19] The large metallic scales and double barbels are features shared by the Chinese dragon, and the large pectoral fins are said to make the fish resemble "a dragon in full flight."[16]
In addition, positive feng shui associations with water and the colours red and gold make these fishes popular for aquaria. All strains are probably endangered, but some (notably the super red and red-tailed golden) more critically than others.[8] The Asian arowana's high value as aquarium fish has impacted its conservation. Other nations restrict or prohibit possession of Asian arowanas; for example, the United States has listed this species under the Endangered Species Act, so it cannot be kept in that country without a permit.[24]
Declining habitat is a major threat.
Care in captivity :
Prepared foods include prawns (shrimp), lean pork, frozen fish food, and pelleted food.[29] Some captive arowanas are fed Koi fry in an attempt to increase the vibrancy of their natural coloration.[30][31]There are over 150 CITES-registered Asian arowana farms in Singapore, Malaysia, Indonesia and other Southeast Asia countries, producing Asian arowana for commercial purpose. Like other arowanas, they need a tight-fitting cover to prevent escape.[23] The water should be well-filtered, soft, and slightly acidic, and maintained at a temperature of 24–30 °C (75–86 °F).[23]
Asian arowanas are carnivorous and should be fed a high-quality diet of meaty food, such as shrimp and crickets. Examples of appropriate live foods include scorpions, centipedes, mealworms, crickets, shrimps, feeder fish, small frogs, and earthworms. They are surface feeders and prefer to take food in the upper parts of the water column. But the actual number of Asian arowana farms in the world could be much higher than that, and probably over 350, of which most may not be registered in CITES yet. They are territorial and may be kept with other Scleropages only in a very large aquarium, provided all fish are of similar size. Because they can grow up to 90 cm (35 in) long, Asian arowanas require large aquaria. The total annual revenue of the Asian arowana sector was estimated at over US$200 million globally. Aquarists recommend live foods and meaty prepared foods.
Types of arowana ;
South American
Water parameters :
However, they do best with water hardness levels of 6.0-7.0 Ph. However, Australian arowanas are known to be able to thrive in cooler temperatures.
As for the water hardness:
Most arowanas are already bred in captive, so they’re able to tolerate a wider range of water hardness. Water parameters should be monitored regularly by using commercially available water test kits.
As a rule of thumb:
Ammonia (NH4): Should be kept at absolutely 0 ppm
Nitrites (NO3): Should be kept at absolutely 0 ppm
Nitrates (NO4): Should be kept below 40 ppm
Filtration :
Newsflash: big fish produce big waste!Arowanas need to consume high-protein food to cope with their rapid growth- and to satisfy their big appetites.
Because of this, they also produce large amounts of waste that could easily pollute your tank’s waters if the filtration system is not up for the job.
While there are a lot of conventional filtration systems available in pet shops around the world, you should only use very efficient and powerful filtration systems for arowanas.
Arowanas are thought of as ‘the holy grail of the tropical fish’ by aquatic hobbyists, so perhaps it should follow that only the best filtration system(s) should be used.
The key component for an arowana-proof filtration system is that it must be able to contain and sustain a lot of ‘biological media’, so as to be able to cope with the large amount of waste these monsters produce.
Here are the top 3 of the best filtration systems to use for arowanas:.
Sump Filter
A Sump filter is an added ‘sump’ tank that holds your filtration media.
It adds another tank designed to circulate your tank’s water towards chambers filled with both biological and mechanical filtration media.
It’s one of the best filtration systems available.
Canister Filter
Relatively small compared to the sump filter, canister filters pressure water from the tank towards the compact filtration system and through the many layers of media within it.
Canister filters are designed to maximize both space and efficiency; just make sure that the canister filter you get is rated for the size of the tank you have.
Trickle Filter
Trickle filters have layer over layer of plastic filtration boxes stacked on top of each other and sitting above your tank.
A pump pushes water through a spray bar pipe which then causes water to trickle over the filtration media within the boxes. This also saves you a lot of space while being able to utilize a large amount of filtration media.
Feeding :
As juveniles, arowanas will readily accept small live fish and other small insects such as worms, roaches and crickets.
You should always consider the size of the prey you will be offering to your fish.
As they grow, you could slowly wean them to accepting non-live frozen foods such as market shrimp, prawns, shellfish, and other meal fish.
Although it’s not easy to achieve, there are some arowanas who would eventually take processed food such as pellets.
However, you must always make sure that the amount protein is sufficient when feeding processed food.
Temperature and suitable tank mates :
There are a lot of species of monster fish, such as the infamous red tail catfish (P. Temperament And Suitable Tank Mates For Arowanas
Aside form the silver and black arowanas, all arowanas are known to be territorial and aggressive.
The Australian is the most aggressive of the bunch and is known to attack and kill all tank mates when they reach 12” or more.
Arowanas are known to attack their own kind as well:
They usually don’t tolerate the presence of other arowanas around them- even if that arowana is of another species.
Because of this, I wouldn’t recommend keeping more than 1 arowana in the same tank, especially for beginners.
But just because they’re aggressive to doesn’t mean that they categorically can’t be kept with any other fish:
The general rule is that the other fish should be big enough not to be eaten, yet docile enough to not bully the arowana.
Popular choices are the peacock bass (Cichla sp.), hooks (Myleus sp.), stingrays (Potamotrygon sp.), big catfish, and other docile monster fish.
Also important to note:
Don’t be too eager to add one monster fish after another. hemioliopterus) and alligator gar (A. Spatula), that could easily outgrow and eat arowanas.
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