Donets Ruffe
The Don ruffe ( Gymnocephalus acerina ) is a Genuine bone fish of the family of the Real perch.
Features
The Don ruffe is less than the high backs kinds of ( traditional ) subgenus Acerina ( with Gymnocephalus ( Acerina ) cernua and Gymnocephalus ( Acerina ) baloni ). He has smaller scales and more Dorsalis stings. It is 25 cm long and has a silvery yellow gray, with irregularly distributed round dark spots of various sizes. D1 with 17-19 spines and three rows of black spots. D2 I/13-15, A II/7-8. These fins and the caudal fin are hardly punctured. 50-54 lateral line scales plus 4-5 undurchbohrte on the slender caudal - peduncle.
Occurrence
The home of Don Kaulbarsches (Russian носарь or бирючок ) is limited to the Black Sea, which opens rivers Don, Dnieper, Dniester, Southern Bug and Kuban - he so on Ukrainian and Moldovan rivers, only the Dnieper River and reached its tributary Pripyat also Belarus. Stray specimens may, for example, in the Danube Delta appear. He is often nowhere and has no economic significance. Originally from days past customer that he was very tasty, but in the Ukrainian population still very much alive.
Way of life
Although this bass is also found in still water and lakes, he still prefers sandy stretches of larger rivers with strong currents ( but he also comes across gravel before ) and live in groups of benthos ( insect larvae, crustaceans, worms, molluscs, little fish ). It is crepuscular and diurnal. In the fall he pulls in larger shoals in deeper water back and survived the winter here inactive. He makes no spawning migration, but spawns a size of about 13 cm ( ie at the age of 2 or 3 years ) in spring in the swarm in the flow over sand or gravel, where the sinking eggs from sticking. At 14 °, the incubation period is ten days but then about 4.5 mm long larvae remain until the exhaustion of the yolk inactive.
System
The Don ruffe differs clearly from other species of the genus Gymnocephalus than this among themselves, so that after Holčík and Hensel ( 1974) ( schraetser Gymnocephalus ) together with the Schrätzer the subgenus Gymnocephalus represented, which was compared with the subgenus Acerina - but recent genetic studies do not support the two morphological sub-genera, so that their existence is unclear.