Family: |
Leuciscidae (Minnows), subfamily: Leuciscinae |
Max. size: |
40.3 cm TL (male/unsexed) |
Environment: |
benthopelagic; freshwater; brackish |
Distribution: |
Europe: Sea of Azov basin in Russia and Ukraine. Landlocked population in Tsimlyansk Reservoir (Don drainage). |
Diagnosis: |
Differs from other species of shemayas by the combination of the following characters: origin of anal fin about 1½ -2½ scales behind dorsal-fin base; anal fin with 15-17½ branched rays; gill rakers 24-28; length of gill raker at angle between upper and lower limbs of first gill arch 30-50% of opposite inner gill filament; lateral line scales 54-64 + 4-5; ventral keel exposed for 4-6 scales in front of anus; head length 21-23% SL; predorsal length 55-57% SL; caudal peduncle depth 9-11% SL,1.7-2.0 times in its length; eye diameter 4.7-5.5% SL, 1.4-1.5 times in interorbital distance; absence of faint grey midlateral stripe; in adult spawners, base of paired fins grey; and presence of numerous small tubercles in nuptial males (Ref. 75106).
Description: dorsal fin with 8½ branched rays; anal fin with 15 -17½ branched rays (Ref. 75106). |
Biology: |
Inhabit lower reaches of rivers, coastal lakes, estuaries, and open sea. Occur close to surface and tolerate salinities up to 12 ppt at the sea. Adults predominantly prey on planktonic crustaceans, terrestrial insects, and small fish. Larvae and young juveniles feed on zooplankton, algae, and insect larvae. Undertake migration for long distances, up to upper reaches of streams in piedmont and montane zones. Spawns in rivers or streams with heavy current on gravel bottom. Landlocked population breeds in reservoir tributaries. Adults migrate back to the sea soon after spawning to forage while young juveniles move downriver in autumn of same year or next spring. Commonly hybridizes with Squalius cephalus. Populations sharply declined in the early and middle 20th century due to the constructed dams that hindered in reaching the spawning grounds. Remaining populations spawn below these dams (Ref. 59043). |
IUCN Red List Status: |
Least Concern (LC); Date assessed: 01 January 2008 Ref. (130435)
|
Threat to humans: |
harmless |
Source and more info: www.fishbase.org. For personal, classroom, and other internal use only. Not for publication.