Butterfly fish
| Butterfly fish | ||||||||||||
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Butterflyfish ( Pantodon buchholzi ) |
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| Systematics | ||||||||||||
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| Scientific name of the family | ||||||||||||
| Pantodontidae | ||||||||||||
| Peters , 1877 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Pantodon | ||||||||||||
| Peters, 1877 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Pantodon Buchholzi | ||||||||||||
| Peters, 1877 |
The butterfly fish ( Pantodon buchholzi ) is a freshwater fish from rivers and streams in tropical West Africa.
features
The butterfly fish becomes 10 to 15 centimeters long. It has a flattened body on the back, which is covered by large round scales. The mouth is large and overhanging, the nostrils tubular. In the side line row (SL) there are 26 to 30 scales, 21 to 26 are located in front of the dorsal fin, which is far back, just in front of the caudal fin. The short dorsal fin is supported by six, the long anal fin by 9 to 15 fin rays. The rear edge of the anal fin is almost smooth-edged in females, but deeply incised in males. The central rays form a tube for internal fertilization. The caudal fin is large, long and frayed at the end. Its two central fin rays are the longest. The fin rays are ringed light and dark in all fins. The pectoral fins are enlarged like wings. With them, he can make gliding jumps up to two meters. The pectoral fins do not flutter. The pelvic fins sit far forward and have four thread-like very long fin rays that are only connected to the fin membrane near the body. The butterfly fish has 30 vertebrae and eight Branchiostegal rays . In the gill cover skeleton the subopercular and sometimes also the interopercular is missing. With the help of the swim bladder , the butterfly fish can breathe air. It is brownish in color.
Occurrence
The butterfly fish lives in disjoint distribution areas in rainforest areas in western Africa. The largest includes the northern and central part of the Congo Basin , another the river basins of the Niger , Benue and Ouémé , and several other rivers from Benin to Cameroon . There are isolated occurrences in Lower Guinea and in the Jong River in Sierra Leone .
Way of life
Pantodon buchholzi lives on the surface of the water in swamps rich in vegetation, jungle pools, streams and quiet sections of rivers. It feeds mainly on insects , but also eats small crustaceans and fish. Insects are mainly taken up from the surface of the water when they have fallen into the water, but can also be preyed on in shallow leaps.
Reproduction takes place after a long courtship, during which the male “rides” for hours on the back of the female and holds on with his pelvic fins. The eggs are fertilized shortly before being deposited in the female's body. The animals turn around each other. During each spawning process, 3 to 7 eggs are laid, a total of 80 to 220. The eggs float on the surface of the water, and the young fish hatch after three days at a water temperature of 25 ° C.
Systematics
Pantodon buchholzi was the German 1877 naturalist and zoologist Wilhelm Peters described and a monotypic genus and family associated with what has been maintained to this day by most authors. Only the Canadian ichthyologist Joseph S. Nelson assigns Pantodon in the fourth edition of his standard work on fish systematics, Fishes of the World , to the osteoglossids (Osteoglossidae). Wilson and colleagues see in Pantodon the sister group of a clade of bones, with the Arapaimidae , while Lavoue and colleagues see Pantodon as a basal genus within the bones, which is in a sister group relationship to all recent bones.
The following cladogram shows the hypotheses about the relationship of the butterfly fish.
| Osteoglossiformes |
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The mitochondrial DNA of the populations of the butterfly fish in the lower Niger Basin and in the Congo Basin differ by 15.2% (for comparison: the total genome of chimpanzees and humans differ by only 1.37%), which leads to the estimate that both populations are around 50 million years ago are genetically isolated from each other and could no longer mix. Morphologically , the two populations do not differ at all. Thus, Pantodon buchholzi may conceal two or more cryptic species .
Keeping in the aquarium
Although Pantodon buchholzi is often offered in pet shops, according to the guidelines of the Heidelberg resolutions on animal welfare in pet shops, it is only partially suitable for keeping aquariums. This is mainly due to its special behavior and food needs. In addition, the species is endangered, since offspring have so far hardly succeeded and thus mainly wild-caught are in the trade.
literature
- Joseph S. Nelson: Fishes of the World , John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
- Günther Sterba : The world's freshwater fish. 2nd Edition. Urania, Leipzig / Jena / Berlin 1990, ISBN 3-332-00109-4 .
- Kurt Fiedler: Textbook of Special Zoology, Volume II, Part 2: Fish . Gustav Fischer Verlag Jena, 1991, ISBN 3-334-00339-6 .
- Sébastien Lavoué, Masaki Miya, Matthew E. Arnegard, Peter B. McIntyre, Victor Mamonekene & Mutsumi Nishida: Remarkable morphological stasis in an extant vertebrate despite tens of millions of years of divergence. Proc. R. Soc., Doi : 10.1098 / rspb.2010.1639
Individual evidence
- ↑ Peters (WCH), 1877. About a strange one from hrn. Professor Buchholz discovered a new genus of freshwater fish, Pantodoon buchholzi, which also represents a new group of fish, Pantodontes, belonging to the Malacopterygii abdominales. Mber. German Akad. Berl. : 195-200.
- ↑ Sebastien Lavoue, John P. Sullivan: Simultaneous analysis of five molecular markers provides a well-supported phylogenetic hypothesis for the living bony-tongue fishes (Osteoglossomorpha: Teleostei). Molecular Phylogenetics and Evolution 33 (2004), page 171-185, PDF
- ^ MVH Wilson & AM Murray: Osteoglossomorpha: phylogeny, biogeography, and fossil record and the significance of key African and Chinese fossil taxa. Geological Society, London, Special Publications January 1, 2008, v. 295, Abstract doi : 10.1144 / SP295.12
- ↑ Sébastien Lavoué, Masaki Miya, Matthew E. Arnegard, Peter B. McIntyre, Victor Mamonekene & Mutsumi Nishida: Remarkable morphological stasis in an extant vertebrate despite tens of millions of years of divergence. Proc. R. Soc., Doi : 10.1098 / rspb.2010.1639
- ↑ http://www.zierfischverzeichnis.de/unghabenet/index.html
Web links
- Butterfly fish on Fishbase.org (English)
- Pantodon buchholzi inthe IUCN 2013 Red List of Endangered Species . Posted by: Moelants, T., 2009. Retrieved January 12, 2014.