River goby
| River goby | ||||||||||||
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A river goby (left), next to it for comparison the darker Kessler goby , both invasive species were caught in the Rhine near Arnhem . |
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| Scientific name | ||||||||||||
| Neogobius fluviatilis | ||||||||||||
| ( Pallas , 1814) |
The Flussgrundel ( Neogobius fluviatilis ) is a species that belongs to the family of gobies belongs (Gobiidae). It occurs in rivers that flow into the Black Sea , the Sea of Azov and the Sea of Marmara (e.g. Southern Bug , Dnieper , Dniester , Don , Danube , Kuban ) and also inhabits shallow areas of the shore of these seas. In the last few decades it has invasively expanded its range further north and has also colonized various rivers in Central Europe.
features
The river goby reaches a maximum length of 20 cm, mostly it remains at a length of 15 to 18 cm. It has an elongated body, the body height is only one sixth of the total length. The head length is one fifth of the total length. The head is stocky, slightly flattened and only slightly wider than it is high. The wide mouth is almost horizontal, the lower jaw protrudes only a little. The lips are comparatively narrow. The length of the tail stalk is greater than its height. The "neck" is scaly, 26 scales are counted between the back of the head and the beginning of the dorsal fin.
- Fin formula : dorsal VII / 14–18, anal I / 12–17, pectoral 12–14.
- Scale formula : mLR 58–65.
River gobies are gray-brown to yellow-brown in color and show numerous, irregular, dark-brown spots and bands on the back and upper sides of the body. A single, dark brown spot is found above the base of the pectoral fins. The dorsal and caudal fins are patterned with numerous brown dots. The males turn black with yellow fin edges during spawning.
Systematics
The closest relatives of the river goby are the black-mouthed goby ( Neogobius melanostomus ) and Neogobius caspius . These three species together form the genus Neogobius . Sister group of this genus are the Benthophilini with 5 kinds. These 8 species are in turn opposed to the 16 species of the Ponticolini , together they all form the subfamily Benthophilinae within the goby family (Gobiidae).
| Benthophilinae |
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Another work that deals with the phylogeny of the entire Gobiidae has confirmed these results in the core, although instead of the Benthophilini the Ponticolini were identified as a direct sister group. The relationship between the three closely related tribes Neogobiini, Benthophilini and Ponticolini is therefore initially unclear.
Way of life
The river goby lives on flat, brackish sea coasts, in estuaries, lagoons and lakes, in medium to large rivers on sandy and muddy bottoms. It is one of the most common fish species in the lower reaches of the rivers it inhabits. It feeds on various invertebrates, especially small crustaceans and molluscs . She can live to be five years old and sexually mature at two. It reproduces from April to July at water temperatures above 13 ° C. They may spawn multiple times in a year. The spawn ball is placed under stones, a mussel, in a snail shell or other hard object and guarded by the male until the larvae hatch.
literature
- Fritz Terofal: Steinbach's natural guide, freshwater fish. Ulmer, Stuttgart 2003, ISBN 3-80014-296-1
Web links
- River goby ( Neogobius fluviatilis ) on Fishbase.org (English)
Individual evidence
- ^ Matthew E. Neilson, Carol A. Stepien: Escape from the Ponto-Caspian: Evolution and biogeography of an endemic goby species flock (Benthophilinae: Gobiidae: Teleostei) . In: Molecular Phylogenetics and Evolution , No. 52, 2009, pp. 91-94.
- ↑ Christine E. Thacker & Dawn M. Roje: Phylogeny of Gobiidae and identification of gobiid lineages . In: Systematics and Biodiversity 9 (4), 2011, pp. 329–347. doi : 10.1080 / 14772000.2011.629011