Nine-spined stickleback
| Nine-spined stickleback | ||||||||||||
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Nine-spined stickleback |
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| Pungitius pungitius | ||||||||||||
| ( Linnaeus , 1758) |
The nine-spined stickleback ( Pungitius pungitius ), also known as the little stickleback , dwarf stickleback or stickleback , is a fish that predominantly lives in small bodies of water .
Like most other stickleback species, the nine-spined stickleback has practically no economic importance. What is remarkable about it, however, is its insensitivity to poor water conditions.
distribution and habitat
The nine-spined stickleback mostly lives in small inland waters, such as ditches and ponds, but also in quiet parts of flowing waters and rivers. It can also be found in brackish and salt water. Flat areas with vegetation are preferred. This stickleback species is quite insensitive to strongly fluctuating water quality, as is typical for small bodies of water.
The distribution area has not yet been fully investigated, but it is certain that it is very similar to that of the three-spined stickleback , but does not extend so far to the south. In northern Germany, significant populations can be found primarily in the catchment areas of the Elbe and Eider and in the Baltic Sea. Inland it could be detected in the Örtze and its tributaries. In southern Germany the nine-spined stickleback lives sporadically in tributaries of the Main . However, these southern occurrences may be due to stocking by aquarists .
Overall, the species is significantly rarer than the three-spined stickleback and is completely absent in the Mediterranean region as well as in Norway and Scotland. In North America, the species occurs in the catchment areas of the Atlantic coast to New Jersey in the south and in the catchment areas of the Arctic Ocean and the Pacific coast of Alaska. The nine-spined stickleback is also found in the Great Lakes .
The populations living in salt and brackish water migrate into fresh water during spawning time.
features
As some of the common names suggest, the nine-spined stickleback remains quite small with a length of five to seven centimeters. His body is slender and compressed on the sides. The eyes are relatively large. The lower jaw of the small and slightly upper mouth protrudes and thus forms the tip of the head. In older males, the mouth rims are bulging and thickened. In front of the soft-radiating dorsal fin are between eight and eleven, but mostly only nine to ten, retractable spines. The pelvic fins each also have a powerful spine. The spines are almost always smooth-edged.
The top of the nine-spined stickleback is gray-green to brown, the sides lighter and shimmering silvery. Animals from the seagrass meadows of the Baltic Sea or waters with a high iron content can show an intense brass sheen. On the flanks there are often irregularly distributed dark spots or cross bands. At spawning time, the body, iris and fin rays of the male specimens take on a dull, more or less intense black. The bright white pectoral fin spines form a striking contrast in the breeding dress. Immediately before spawning, the male's genital papilla also takes on this white color. Regarding the coloring at the spawning season, there are also deviating observations, for example greenish tones on the belly and reddish tones on the head.
The typical family signage on the sides of the body is different depending on the population. In the nominate form it is reduced to a few weakly keeled bone plates on the tail stalk. Only one subspecies is fully signposted, one subspecies is completely naked. The nine-spined stickleback has ten to 14 gill fangs .
- Fins formula : dorsal 1 IX-X (VIII-XI), dorsal 2 10-12, anal I / 9-11, pectoral 9-10, ventral II / 1, caudal 12
behavior
The nine-spined stickleback feeds mainly on invertebrates, eating almost everything from them that it can overwhelm.
The reproductive behavior of the nine-spined stickleback is similar to that of its larger relative, the three-spined stickleback . However, the barrel nest is generally not built on the ground, but mostly hung between plants.
Outside the breeding season, the nine-spined stickleback lives mainly solitary and is noticeably shy. In the event of imminent danger, he tries to hide in the mud or vegetation. During the escape, he also tries to stir up mud by touching the ground and thus "darken" the attacker's view.
Males are usually only three years old, the females can reach five years.
Subspecies
Internally, the nine-spined stickleback is further differentiated into several subspecies, these differ mainly in terms of distribution area and signage. The taxonomic problems are considerable, however, so that the structure is subject to frequent changes. Keivany and Nelson distinguish the following subspecies:
- P. pungitius pungitius
- P. pungitius laevis
- P. pungitius occidentalis
- P. pungitius sinensis
- Sakhalin stickleback ( P. pungitius tymensis )
The last two forms, both from East Asia, can be clearly distinguished from P. pungitius pungitius by DNA comparisons and are now considered to be separate species.
Web links
- Nine-spined stickleback on Fishbase.org (English)
- Pungitius pungitius inthe IUCN Red List of Threatened Species 2013.2. Listed by: NatureServe, 2012. Retrieved January 27, 2014.
swell
literature
- Hans-Joachim Paepke: The sticklebacks: Gasterosteidae , Westarp Sciences, Magdeburg 1996, ISBN 3-89432-492-9
- Günther Sterba : Freshwater fish of the world , Weltbild Verlag, Augsburg 1998, ISBN 3-89350-991-7
- Urania Tierreich - fish amphibians reptiles , Urania Verlag Leipzig / Jena / Berlin, 1967
- Horst Müller: European fish , Neumann Verlag, Leipzig · Radebeul 1983, ISBN 3-7402-0044-8
- Rudolf Suttner: The nine-spined stickleback , the aquarium, 11/2005 p. 4–10, Birgit Schmettkamp Verlag, ISSN 0341-2709
Individual evidence
- ↑ Yazdan Keivany & Joseph S. Nelson: Taxonomic review of the genus Pungitius, ninespine sticklebacks (Gasterosteidae) (engl., Pdf; 535 kB)
- ↑ Hiroshi Takahashi, Peter R. Møller, Sergei V. Shedko, Temirbekov Ramatulla, Sang-Rin Joen, Chun-Guang Zhang, Valentina G. Sideleva, Keisuke Takata, Harumi Sakai, Akira Gotoi, Mutsumi Nishida: Species phylogeny and diversification process of Northeast Asian Pungitius revealed by AFLP and mtDNA markers. Molecular Phylogenetics and Evolution, 2016, doi: 10.1016 / j.ympev.2016.03.022
- ↑ Pungitius sinensis on Fishbase.org (English)
- ↑ Pungitius tymensis on Fishbase.org (English)