Bullhead
| Bullhead | ||||||||||||
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Bullhead |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Romanichthys | ||||||||||||
| Dumitrescu, Bănărescu & Stoica, 1957 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Romanichthys valsanicola | ||||||||||||
| Dumitrescu, Bănărescu & Stoica, 1957 |
The Gropp perch ( Romanichthys valsanicola ) in Romance languages also Asprete called, is a small flussbewohnender perch (Percidae), the Central romania north of the Danube, the river system of Arges and its tributaries Valsan and Riul Doamnei (woman river), as endemic was widespread . Its habitat is now limited to a small section of the Vâlsan River.
features
The fish is 10 to a maximum of 15 centimeters long and has small, rough scales. Its color is marbled gray and brown.
Because of its biological similarity ( convergence ) with the bullhead ( Cottus gobio ) it was first described in 1957 and was given the German book name "Groppenbarsch". Seen from above, with its broad head it actually looks very similar to a bullhead female. It has always been known to the locals as asprete (from Latin asper "rough", cf. also the related fish Zingel asper , because of the roughness of the scales). In contrast to bullheads, its mouth is smaller, somewhat lower and arched. The caudal fin is incised, so two-lobed, not round like the bullhead.
Fin formula : D1 VIII-IX, D2 I-II / (13) 14-16, AI / 7, PI / 12-13; 58–68 lateral line scales .
Way of life
The species prefers cold, clear mountain waters with fast currents. During the day it hides under stones, where it is well camouflaged by its color. Their movements are only a few meters during the day. Mainly at night it searches the ground, mostly over gravel and gravel, for insect larvae living in the water. The species feeds mainly on stonefly , caddis flies and mayfly larvae .
The spawning season is between May and June. 120 to 150 eggs are laid on rocks and under stones. The surface of the whitish-translucent eggs has a honeycomb-like structure.
Distribution area and endangerment
The bullhead bass has been called the most critically endangered fish in Europe since 1991. Before the beginning of the Ice Age it was widespread in the Palearctic , after the end of the Ice Age a relic area remained in the upper reaches of some tributaries of the Danube in Romania. From most of this distribution area it has recently been displaced by harmful sewage, gravel extraction and dams. It is very likely that there is also a competitive relationship with Cottus, which lives in the same biotope . After the construction of the 166-meter-high Vidraru Dam in 1965, the populations in the dammed Argeș and the Râul Doamnei, a smaller tributary of the reservoir, died out. There is not enough water below the dam to ensure the survival of the fish species. Only in a tributary of the Argeș, the Vâlsan, located further to the south, there is a roughly 1 km long stretch of river above the village of Bradet , which serves as a retreat for the species. The river Vâlsan was also dammed in the upper reaches, so that the remaining population is dependent on the continuous supply of water from the reservoir. Romanichthys valsanicola became the fish species with the smallest distribution area in Europe through these construction measures. In 1995 the total population was estimated to be less than 100 individuals. In the habitat that exists today, the species is impaired by flooding due to its small number of individuals , which drifts the spawn and fish into river stretches that are unsuitable for survival. Measures to maintain Gropp perch were from 1999 by an EU - LIFE funded program. The Federal Agency for Nature Conservation in Bonn carried out successful breeding trials. The species has been classified as critically endangered by the IUCN since 1996.
Taxonomy and systematics
Romanichthys valsanicola is monotypical, ie it is the only species in the genus Romanichthys . This was built in 1957 at the same time as the first description of the species and means something like "Romanian fish". The type epithet valsanicola indicates its occurrence in the Vâlsan.
Its anatomy suggests a derivation of Sander and Zingel ancestors, which is also supported by phylogenetic studies. With these two genera Romanichthys valsanicola is summarized within the real perch to the subfamily Luciopercinae .
Individual evidence
- ↑ a b c d Adrian Ionascu: Use of behavioral ecology in the conservation of an endangered fish species: asprete (Romanichthys valsanicola Dumitrescu, Banarescu, Stoica 1957), the rarest freshwater fish in Europe. MAB Secretariat, Division of Ecological Sciences, UNESCO, 2004 PDF (English)
- ↑ a b R. Riehl and Rüdiger Bless: First report on egg deposition and egg morphology of the endangered endemic Romanian perch. Journal of Fish Biology, 46, 6, pp. 1086-1090, June 1995 doi : 10.1111 / j.1095-8649.1995.tb01412.x
- ↑ Petru Banarescu, Rüdiger Bless and Adrian Georgescu: Threatened fishes of the world: Romanichthys valsanicola Dumitrescu, Banarescu and Stoica, 1957 (Percidae). Environ. Biol. Fish. 43, 2, p. 144, 1995 doi : 10.1007 / BF00002482
- ^ J. Freyhof & M. Kottelat: Romanichthys valsanicola . In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. Retrieved December 14, 2010
- ↑ Choon Bok Song, Thomas J. Near and Lawrence M. Page: Phylogenetic Relations among Percid Fishes as Inferred from Mitochondrial Cytochrome b DNA Sequence Data. Molecular Phylogenetics an Evolution, 10, 3, pp. 343–353, 1998 PDF (English)
literature
- M. Dumitrescu, P. Bănărescu and N. Stoica: Romanichthys valsanicola nov. gen. nov. sp. (Pisces, Percidae). Trav. Mus. Hist. Nat. 'Grigore Antipa', 1, pp. 225–244, 1957, p. 230. (first description)
- Uwe Hartmann and Gunter Steinbach: Steinbach's natural guide for freshwater fish. 3. Edition. Ulmer Verlag, Stuttgart 2010 ISBN 3-8001-5936-8 .
Web links
- Groppenbarsch on Fishbase.org (English)
- Freyhof, J. & Kottelat, M. 2008. Romanichthys valsanicola in IUCN Red List of Threatened Species