Back swimming Congo cat
| Back swimming Congo cat | ||||||||||||
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Back swimming Congo Catfish ( Synodontis nigriventris ) |
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| Scientific name | ||||||||||||
| Synodontis nigriventris | ||||||||||||
| David , 1936 |
The back swimming Congo catfish ( Synodontis nigriventris ) belongs to the family of the whiskered catfish (Mochokidae). It lives in the plant-rich banks of larger rivers and swamps of the Congo rainforest .
features
The back-swimming Congo cat corresponds in its habitus to the other species of the genus Synodontis . The males are up to 9.6 cm long, the females are fuller, especially when they are mature enough to spawn. The fish is flattened on the sides and high-backed, like other catfish it has no scales. He wears three pairs of barbels on his mouth, the two of which on the lower jaw are feathered. The latter are typical for the entire genus and have given it the name Fiederbartwelse. Typical of the species is the small distance between the eyes and the dark to black belly, which gave this species the scientific name nigriventris (= "black bellied"). The rest of the body color is light gray to cream-colored with distinct, dark brown to black spots that can also stand together in bands.
The basic color of the fins of the fish is colorless and covered with black spots. The dorsal fin (dorsal) and the pectoral fin (pectoral) each have a strong hard ray designed as a thorn. The spine of the dorsal fin is in this species, unlike other species of the genus, smooth and imperforate on the front, followed by seven soft rays, the anal fin (anal) consists of four undivided and four to seven divided soft rays. The large, long adipose fin is also striking.
distribution and habitat
The back swimming Congo cat is common in the entire river system of the Congo Basin . The tropical waters are structured and shaded and have a temperature of around 25 ° C with a pH value of 6.0 to 7.0.
Way of life
This type of habit owes its common name to the habit of mostly swimming with one's stomach up. The pigmentation is adapted to this behavior and the belly side is darker than the back. As a result, they can be more difficult to detect by potential predators such as birds, larger fish and mammals against the bottom of the water or against the surface of the water. In addition to the species S. nigriventris , which exercises excessive backstroke swimming, there are also some other species in the genus Synodontis known that sometimes swim in the supine position, such as B. Synodontis eupterus . Backstroke swimming is also known from juvenile fish of the species S. batensoda and there is also a backstroke swimmer in Asian spiny catfish (family Bagridae ) with Heterobagrus leucophasis .
food
The food of the back swimming Congo Catfish consists of small crustaceans and plant material. However, the Congo catfish also like to eat the insects that fall from the bank vegetation into the water. As a rule, food is also consumed by swimming on the back. Accordingly, the fish either swim directly below the surface of the water or graze on the algae growth on the underside of the leaves of aquatic plants; feeding from the bottom is rare, but also possible.
Reproduction and development
Eggs are laid in specially protected, dark areas of the water, where up to 450 eggs are glued to the substrate. The fry hatch after about a week, the fry lose the yolk sac after about four days. For the first few weeks they swim in the position that is usual for most catfish and only after about seven weeks do they move into the typical supine position.
Aquaristics
The back swimming Congo Cat is a fish that is often kept in aquariums and is of particular interest to aquarists because of its unusual way of swimming for catfish. As a rule, it is described as an undemanding and easy-to-keep species that can also be grown in aquariums. It is described, however, that offspring are rare and mostly occur randomly. Other sources mark the back-swimming Congo Cat as susceptible to poor water values and to white spot disease . According to the Heidelberg resolutions of the Zentralverband Zoologischer Fachbetriebe Deutschlands e. V. (ZZF), keeping the species is not recommended and, like all species of the genus, is listed on the Red List.
literature
- Günther Sterba : Freshwater fish in the world . Weltbild Verlag, Augsburg 2004, ISBN 3-89350-991-7 .
Web links
- Back swimming Congo Wels on Fishbase.org (English)
- www.scotcat.com: Synodontis nigriventris
- Synodontis nigriventris in the Red List of Threatened Species of the IUCN 2013.2. Posted by: Moelants, T., 2009. Retrieved January 10, 2014.
Individual evidence
- ↑ Information according to Sterba for aquarium keeping and 25 ° C water temperature
- ↑ http://www.scotcat.com/factsheets/s_nigriventris.htm
- ↑ List of ornamental fish
- ↑ Heidelberg resolutions of the ZZF on animal welfare in pet supplies Status: February 8, 2006 (pdf) ( Memento of the original from September 29, 2007 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
