Rutilus caspicus (Yakovlev, 1870)
Caspian roach

Family:  Leuciscidae (Minnows), subfamily: Leuciscinae
Max. size:  45 cm SL (male/unsexed); max.weight: 2,000.0 g; max. reported age: 10 years
Environment:  benthopelagic; freshwater; brackish
Distribution:  Eurasia: Northern and northwestern Caspian Sea; enters Volga, Ural, Emba, Terek and Kura drainages for spawning.
Diagnosis:  Can be diagnosed from its congeners in Caspian Sea basin by having the following characters: 39-48 (usually 42-44) scales along the lateral line; body laterally compressed, depth 24-37% SL; dorsal fin usually with 9½ branched rays; anal fin usually with 10½ branched rays; mouth subterminal; snout rounded; iris silvery grey; pectoral pelvic and anal fins grey with dark margins (sometimes slightly red in autumn, outside spawning season); breeding males with fine, scattered tubercles on top and side of head (Ref. 59043)
Biology:  A semi-anadromous species which occurs mostly in shallow brackish coastal waters. During summer at the sea, adults are most abundant at water depth of 2.5-4.0 m and salinity of 2-4 ppt. Enters freshwater of estuaries, lagoons and lower reaches of large rivers to spawn. In rivers, juveniles take plankton (mostly Cladocera) and small benthic animals as food. At the sea, they feed on oligochaetes, chironomid larvae and algae. Adults also prey on crustaceans, worms and chironomids larvae. Spawns on shallow shores of coastal lakes and flooded areas. After spawning adult move back to the sea to join groups of immature juveniles, not traveling for long distances, staying in areas with high abundance of prey. Larvae migrate to the sea (Ref. 59043).
IUCN Red List Status: Least Concern (LC); Date assessed: 01 January 2008 Ref. (130435)
Threat to humans:  harmless


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