Blue catfish

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Blue catfish
Drawing from the first description by Rudolf Kner

Drawing from the first description by Rudolf Kner

Systematics
Order : Catfish (Siluriformes)
Subordination : Loricarioidei
Family : Armored catfish (Loricariidae)
Subfamily : Ancistrinae
Genre : Antennae armor catfish ( Ancistrus )
Type : Blue catfish
Scientific name
Ancistrus dolichopterus
Kner , 1854
Catfish on a coconut shell
Female Ancistrus -Wels
Female Ancistrus -Welse compete Cave
Blue catfish close-up

The blue catfish ( Ancistrus dolichopterus , syn .: Hypostoma punctatum Jardine , 1841 , Xenocara dolichoptera ( Kner , 1854) ) or white- necked catfish, in English Bushymouth catfish, is a species from the genus of the antenna armor catfish ( Ancistrus ) within the armor catfish family (Loricariidae). Despite the German species name, the species does not belong to the family of the antenna catfish (Pimelodidae).

As an aquarium fish , the blue antenna catfish was brought to Germany by two Hamburg importers in 1911. It is also defined with the L number "L 183". In 1988, Rainer Stawikowski, Arthur Werner and Uli Schliewen introduced the code system of the L-numbers because of the diversity and unmanageability of imported, but not yet scientifically described, antenna-armored catfish, in order to temporarily organize and define these taxa introduced for aquarists. The "L" is derived from the family name Loricariidae (armor catfish), the number refers to the order of publication in DATZ .

features

In captivity, the blue catfish can reach a length between 15 and 25 centimeters and, under ideal conditions, a life expectancy of 15 years. The females are usually slightly smaller than the males. The basic color is a dark black that fades easily with age. The entire body is covered with small white dots. The dorsal and caudal fins have a white border, which in contrast to the very similar Ancistrus sp. L181 ( L number ) mostly not faded. The Ancistrus dolichopterus can also be distinguished from the other species with mostly 7 soft rays based on the 8–9 soft rays of the dorsal fin. Like all armored catfish, the blue catfish also has interopercularodontodes and odontodes.

As is typical for the species, the males develop antlers from fleshy appendages near their mouths, which also grow to the forehead. The females of Ancistrus dolichopterus also have outgrowths, but much smaller and only around the mouth. Therefore, a differentiation between the sexes is only possible from a certain size.

habitat

It is native to the Rio Negro , a tributary of the Amazon in South America . Typical of this river is the black water , which is partly clear, but partly colored from amber to dark brown by tannins. Rio Trombetas , Rio Tefé , Rio Madeira and Rio Tapajós also belong to its habitat . The species is also found in rivers such as the Rio Padauiri (Barcelos District), Rio Demini, Rio Branco and the Rio Nhamundá , behind stones or in dead wood. But it can also occur in clear water and white water rivers. Ancistrus dolichopterus prefers very soft water with a low pH and temperatures of 26-29 ° C. This species has not yet been able to establish itself as an invasive species in the USA. In Germany one finds a small stable population in the Gillbach (hot water discharge from a power station), in the Wassergarten von Reden (discharge of swamp water from coal mining) and in the Warmbach in Austria near Villach .

food

He is herbivorous and a growth eater. He rasps his food, mostly bacterial or algae deposits, mainly with his teeth from smooth surfaces such as stones and soft root wood. This wood is needed for their intestinal flora. He consumes both vegetable and animal food. In captivity, feeding with frozen food, vegetables (cucumber, bell pepper, zucchini) and special catfish chips is successful. After long periods of rest, the fish start looking for food on surfaces. This is where the name “disk cleaner catfish” comes from.

Reproduction

Like all antenna catfish, it spawns as a hideout in caves and under roots. These caves also serve as a place of retreat, since the fish is more active at night in strong lighting. Catfish caves and other shelters should always be available in sufficient numbers, otherwise they will be fought over. The eggs are about 3 mm in size and clearly orange in color. The female lays up to 90 eggs in clutch balls. The male takes care of the brood and constantly fills the clutch with fresh water. Once a pair has been found, the female spawns every 21 days under good conditions. The young hatch after about 5 days. After about 14 days, the yolk sac has receded. Under ideal conditions, Ancistrus catfish can reproduce very strongly.

attitude

Although it is generally possible to keep it alone, Ancistrus dolichopterus should be kept in a small group. A group of one dominant male and two to three females has proven itself. The fish are usually peaceful, but there can be rivalries between competing males and fights over territories and females. A structural subdivision of the basin leads to less turf wars. Larger fish are also extremely assertive when it comes to feeding. The blue catfish feels at home in weakly acidic water with pH values ​​between 4.0 and 4.5 and water temperatures between 24 and 30 ° C with a dark substrate. The acidic environment of the water can be achieved by adding leaves or humic substances . The addition of oak , willow or alder bark , alder cones , walnut shells , sea almond leaves, sea almond bark , oak leaves, beech leaves or even lignite can lower the pH of the aquarium and create a bacteriostatic environment that improves fish health. Sand and fine gravel simulate the sandbanks of the Rio Negro. Due to its relative size, the species has a certain space requirement, so the edge length of the aquarium should not be less than 80 centimeters. To keep the animals healthy, the water should be partially changed weekly, depending on the water quality. The blue catfish is sometimes sensitive to the bacterial load in the aquarium water. In larger pools, however, the water values ​​remain more stable. An ideal pool setup includes numerous hiding places such as clay pipes, stones, slabs, bog roots, halved coconut shells and sunken flower pots. Offspring is only possible with varied feeding and optimal water values. The ornamental fish export of Ancistrus dolichopterus is currently on the official Brazilian positive list.

Hazardous situation

The International Union for Conservation of Nature IUCN lists the antenna catfish in the Red List of Endangered Species under Least Concern , so it is not considered endangered.

relationship

The animals are difficult to distinguish from the similar Ancistrus sp. L 181 to be distinguished. Only the number of soft rays of the dorsal fin and the disappearing white border of the L 181 allow a distinction. It is believed that there are hybrids of both species. Animals with eight soft rays and edges that tend to fade late suggest this assumption.

Common to all antenna catfish are the typical antler-shaped growths on the forehead of the male animals.

In the aquarium hobby, another Ancistrus species or hybrid is usually maintained and propagated under this species name .

Individual evidence

  1. ↑ a b c d e f g h Aquarium guide Ancistrus dolichopterus
  2. ↑ Ancistrus dolichopterus Kner, 1854. Bushymouth Catfish on Fishbase
  3. ↑ l-welse.com
  4. ↑ a b c d e f g L catfish Ancistrus dolichopterus
  5. ^ Distribution of Ancistrus dolichopterus Kner, 1854
  6. ↑ a b c d e f catfish database
  7. ↑ Bushymouth Catfish (Ancistrus dolichopterus). Ecological Risk Screening Summary. US Fish and Wildlife Service. 2018
  8. ↑ a b https://www.neuebrehm.de/uploads/books/755/Leseprobe.pdf Michael Kempkes, Juliane Lukas and David Bierbach: Tropical neozoa in domestic rivers. Guppies and other exotic species in Gillbach and Erft - causes, consequences, perspectives. NBB compact. 2018
  9. ↑ Jürgen Petutschnig, Wolfgang Honsig-Erlenburg, Reinhard Pekny: To the current crayfish and fish occurrence of the Warmbach in Villach. In: Carinthia II . 198/118 Year, Klagenfurt 2008, pages 95-102 ( PDF on ZOBODAT ).
  10. ↑ Examples of catfish caves
  11. ↑ Problem animals that are given away frequently
  12. ^ Community keeping of cichlids, mullets and catfish
  13. ↑ Humic substances - the unknown miracle weapon in the aquarium
  14. ↑ IBAMA . Diário Oficial da Uniao. Ministério da Pesca e Aquicultura ( suedamerikafans.de PDF).
  15. ↑ Ancistrus dolichopterus in the endangered Red List species the IUCN 2009. Posted by: R. Rice and F. Lima, 2007. Accessed on March 6 of 2010.
  16. ↑ list of ornamental fish

Web links

Commons : Blue catfish ( Ancistrus dolichopterus )  - Collection of images, videos and audio files