Romanichthys valsanicola
The Gropp perch ( Romanichthys valsanicola ), called in Romance languages also Asprete, is a small flussbewohnender perch ( Percidae ), the Central Romania north of the Danube, in the river system of the Arges River and its tributaries VALSAN and Riul Doamnei (woman river), was used as endemic. Meanwhile his habitat on a small section of the river VALSAN is limited.
Features
The fish is 10 up to 15 inches long and has small, rough scales. Its coloration is mottled gray and brown.
Because of its biologically great similarity ( convergence ) with the bullhead ( Cottus gobio ), it was first described in 1957 and was awarded the German-language book called " Gropp perch ". Viewed from above, he sees with his broad head a bullheads females actually very similar. The locals, he was Asprete ( see also the related fish Zingel asper, from Latin asper " rough " because of the roughness of the scales) known ever since. In contrast to bullheads its mouth is smaller, somewhat inferior and arcuate. The caudal fin is cut, so bilobed, not rounded as in the bullhead.
Fins 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 lakes and fast-flowing. She hides during the day under stones, where it is well camouflaged by their coloring. Their movements be during the day only a few meters. Mainly at night she studied the ground, mostly on dirt and gravel, off to the aquatic insect larvae. The species feeds mainly on stoneflies, caddisflies 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 white- translucent eggs has a honeycomb structure.
Area of distribution and hazard
The Gropp perch is referred to as the most endangered fish in Europe since 1991. Before the start of the Ice Age, he was widely used in the Palaearctic, after the end of the Ice Age remained a relic area in the headwaters of some tributaries of the Danube River in Romania. For the most part, this distribution area he was ousted recently by harmful effluents, gravel withdrawals and dams. Very likely, there is also a competition ratio for living in the same habitat Cottus. - After the construction of the 166 meter high dam Vidraru in 1965 extinguished the populations in the pent Arges and Raul Doamnei, a smaller tributary of the reservoir. Below the dam too little water is present to ensure the survival of the species. Only in a more southern tributary of the Arges, the Valsan, there above the village Bradet still a 1 km long river section which serves as a retreat for the nature. The river VALSAN but was also jammed in the upper reaches, so that the remaining population of the continuous water supply from the reservoir depends. Romanichthys valsanicola was through this construction to the species with the smallest distribution area in Europe. In 1995, the total stock was estimated at less than 100 individuals. In its existing today habitat, the species is due to their small numbers of individuals by each flood affected, the drifts the spawning and the fish in order to survive unsuitable river routes. Measures for the conservation of Gropp perch were funded from 1999 by an EU LIFE program. The Federal Agency for Nature Conservation in Bonn led by successful breeding attempts. The species is classified endangered by IUCN since 1996 as endangered ( " Critically Endangered ").
Taxonomy and systematics
Romanichthys valsanicola is monotypic, ie it is the only species in the genus Romanichthys. This was built in 1957 simultaneously with the first description of the nature and means something like " Romanian fish ". The specific epithet valsanicola points to its occurrence in VALSAN.
Its anatomy suggests a derivation of Sander and zingel ancestors, which is also supported by phylogenetic analyzes. With these two genera Romanichthys valsanicola is summarized within the Real perch to the subfamily Luciopercinae.