Chondrostoma variabile Yakovlev, 1870
Volga undermouth

Family:  Leuciscidae (Minnows), subfamily: Leuciscinae
Max. size:  35 cm TL (male/unsexed); max. reported age: 7 years
Environment:  benthopelagic; freshwater; brackish
Distribution:  Europe and Asia: Capian basin, in Emba, Ural and Volga drainages (with Oka and Kama); Black Sea basin, in Don drainage.
Diagnosis:  Diagnosed from congeners in Black and Caspian Sea basins by having straight or slightly arched mouth, 9½ branched dorsal rays, 50-62 scales on lateral line, usually 10½ branched anal rays, and large eye, diameter 50-65% of interorbital distance (Ref. 59043).
Biology:  Occurs in lowland and piedmont rivers with moderate to strong current and in reservoirs. Commonly found in river main courses in rapids, sandy shallows and river curves. Larvae and juveniles with superior mouth prey on small invertebrates. After 3-4 months, juveniles measuring about 3-3.5 cm SL change to adult feeding mode and graze benthic diatoms and detritus from hard substrate in habitats with strong currents. Breeds on gravel or rock bottom in shallow riffles of larger rivers or in smaller tributaries with moderate to strong current. Most of the year in the middle and upper stretches of rivers, moves to lower stretches or to larger tributaries during winter. Deposits sticky eggs which adhere to gravel. (Ref. 59043).
IUCN Red List Status: Least Concern (LC); Date assessed: 01 January 2008 Ref. (130435)
Threat to humans:  harmless
Country info:   
 


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