The Volga undermouth or Volga nase (''Chondrostoma variabile'') is a species of

cyprinid Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest ver ...

freshwater fish. This one lives in the Emba,

Ural Ural may refer to: *Ural (region), in Russia and Kazakhstan *Ural Mountains, in Russia and Kazakhstan *Ural (river), in Russia and Kazakhstan * Ual (tool), a mortar tool used by the Bodo people of India *Ural Federal District, in Russia *Ural econ ...

and

Volga The Volga (; russian: Во́лга, a=Ru-Волга.ogg, p=ˈvoɫɡə) is the longest river in Europe. Situated in Russia, it flows through Central Russia to Southern Russia and into the Caspian Sea. The Volga has a length of , and a catchm ...

drainages of the

Caspian Sea The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...

basin, and the

Don River The Don ( rus, Дон, p=don) is the fifth-longest river in Europe. Flowing from Central Russia to the Sea of Azov in Southern Russia, it is one of Russia's largest rivers and played an important role for traders from the Byzantine Empire. Its ...

drainage of the

Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Rom ...

basin. It is a riverine fish but is also found in reservoirs. The distribution is in lowland areas and foothills, and the fish prefer river stretches with strong currents, including rapids. Larvae and juveniles have a superior mouth, but at 3–4 months they change to adult feeding mode (undermouth) and start grazing the bottom, eating benthic diatoms and detritus from hard substrate. Breeding females deposit sticky eggs on gravel bottom in shallow parts of rivers with moderate to strong current.

References

* * Chondrostoma Fish described in 1870 Taxa named by Vasily Evgrafovich Yakovlev {{Leuciscinae-stub