Giant tiger tetra
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Giant tiger tetra ( Hydrocynus goliath ) |
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| Hydrocynus goliath | ||||||||||||
| Boulenger , 1898 |
The giant tiger tetra ( Hydrocynus goliath , syn .: Hydrocynus vittiger , Hydrocyon vittiger ), also giant tiger fish , Goliath tiger tetra or water dog (English: Giant tigerfish ) is a freshwater fish and the largest species of the African tetra family (Alestidae) .
distribution
The giant tiger tetra is widespread in the west and central African Congo and its catchment area. Thus it also occurs in the Lualaba River, Upemba and Tanganyika lakes , but is absent in all other electricity systems on the continent.
features
Giant tetras are elongated, strong fish with a spindle-shaped shape. The head is big and strong. The caudal fin is large, deeply forked and with a very strong caudal stalk. In the subadult stage, the animals are rather elongated with a reddish coloration of the lower caudal lobe (tail lobe ), which disappears by the adult stage. They also get higher and higher back with age. Longitudinal stripes, which are typical for other tiger fish species, are only very weak or completely absent. There are no known gender differences. Lengths of well over a meter and weights of several dozen kilograms are achieved. There are also unconfirmed reports of specimens 180 cm in length. The most striking feature is probably its terrifying set of teeth, because the terminal and deeply split mouth is densely covered with large, needle-sharp, interlocking teeth. In shape, the teeth are triangular with razor sharp edges. Another very interesting feature is their second joint in the upper jaw, which allows the fish to open their mouths much wider.
Way of life
As active hunters they usually stay in strong currents. Since they mostly live in very murky water, they have a well-developed lateral line that makes it easier for them to catch prey. They live exclusively piscivor and also snap at conspicuously large prey fish, from which they can tear pieces with their teeth. As a rule, however, prey is preferred, which can be devoured whole. Larger specimens seem to live solitary, while the juveniles come together in smaller groups. According to the people who live there, this is the only fish that is not afraid of crocodiles.
Hydrocynus goliath and man
Attacks on people
Multiple attacks on humans by the giant tiger tetra have been reported. The animals sometimes jumped out of the water. They seem to react aggressively to splashing in the water and glittering objects.
The natives of the Republic of the Congo attribute these attacks to the evil spirit "Mbenga", who is said to live in the fish.
Economical meaning
The locals use the giant tiger tetra as food fish just like all other fish species. Nevertheless, you will not be able to buy it very often for your own kitchen, although it is a very good food fish. However, due to its appearance and fighting strength, it is popular prey in fishing. Various bookable fishing trips to the Congo are offered to chase these fish.
Aquarium keeping
A few aquarists keep giant tiger tetra in larger tanks. The water parameters are only of minor importance for maintenance. Water that is not too cold, oxygen-rich and with the strongest possible current is important. Good filtration and regular water changes are necessary, as larger amounts of nitrate are not so well tolerated. Tiger fish are very sensitive to drugs with added dyes, so if they are infected with ectoparasites it is better to treat them with iodine-free table salt and increase the temperature. Due to the attainable body size, only correspondingly large aquariums are suitable for keeping these agile, swimming predators. A lot of free swimming space and some spacious shelters are not unimportant. Caution is advised when handling larger specimens in the basin. The animals bite extremely quickly, food tweezers or similar are essential. Breeding in the aquarium has not yet been successful.
literature
- K. Arendt (1999): An African tiger tetra, Hydrocynus cf. goliath. Aquaristik Fachmagazin, 31 (5): 19-20 (Species: Hydrocynus vittatus d.Aut.)
- B. Brewster (1986): A review of the genus Hydrocynus Cuvier, 1819 (Teleostei: Characiformes). Bull.Br.Mus. (Nat.Hist.) Zool .., 50 (3): 163-206
- D. Dann (undated): The largest Tigerfish in the world - the Goliath. Bugzer Europe SA, Brussels: 119 pp.
- J. Géry (1978): Characoids of the world. TFH Publications, Neptune City.
Web links
- http://www.aqua-terra-net.de/Hydro/Sonder/salmler/Hydrocynus%20goliath.htm
- http://diskusmann.de/stec/aqua/afri/navi_stec_aqua_afri_hydrocynus_goliath.htm
- Hydrocynus goliath ( Memento from June 21, 2010 in the Internet Archive )
- Hydrocynus goliath - Boulenger, 1898 - Giant tigerfish ( Memento from August 15, 2011 in the Internet Archive )
- Hydrocynus goliath inthe IUCN 2013 Red List of Threatened Species . Posted by: Moelants, T., 2009. Retrieved January 9, 2014.
- Monster fish? Those are the ones with the extra teeth. DIE WELT , accessed on May 14, 2015 .