Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic; depth range - m (Ref. ), usually - m (Ref. ). Temperate; 0°C - ; 60°N - 40°N
Europe: central and eastern Europe and northern Asia Minor (Ref. 57778). Basins of North, southern Baltic, Black, western and southern Caspian and Aegean Seas (from Maritza to Struma drainages); Mediterranean basin, only in northern Rhône (France) and Drin drainages (Alabania, Montenegro, Macedonia). Abundant and expanding in most of its range, but locally threatened by water pollution, weed clearing, and stocking of predatory fish (Ref. 59043).
Length at first maturity / Size / Weight / Age
Maturity: Lm 5.5, range 3 - 6 cm
Max length : 11.2 cm TL male/unsexed; (Ref. 88166); common length : 5.0 cm TL male/unsexed; (Ref. 556); max. reported age: 5 years (Ref. 9696)
soft rays: 8 - 10;
Vertebrae: 34 - 36. Caudal fin with 19 to 20 soft rays. Differs from Rhodeus meridionalis by having sub-inferior mouth (vs. terminal), rostral cap covering all or at least more than half of upper lip (vs. only upper part of upper lip) (Ref. 59043).
Occurs most abundantly in still or slow-flowing water with dense aquatic vegetation and sand-silt bottom as lowland ponds, canals, slow-flowing rivers, backwaters and oxbows, where mussels are present (Ref. 59043). Found among plants over sand and muddy bottoms in shallow waters. Remarkable for its habit of deposing its eggs in the cavity of bivalves (Unio). Feeds mainly on plants and to a lesser degree on worms, crustaceans, and insect larvae. Formerly used for pregnancy tests: females injected with urine from pregnant women protruded their ovipositors (Ref. 6258). Live span is exceptionally up to 5 years but most individuals do not survive the year of their first reproduction and population sizes fluctuate greatly over the years (Ref. 59043).
Spawns in clear, slow-running or still water, often with a muddy bottom. The presence of nearby freshwater mussels is of vital importance. Female deposits eggs within the valves of the mussel. Male sheds sperm into the inhalent current of the respiring mussel and thereby, fertilizes the eggs. Fry remain in the mussel until protection is not anymore required.
Kottelat, M. and J. Freyhof, 2007. Handbook of European freshwater fishes. Publications Kottelat, Cornol and Freyhof, Berlin. 646 pp. (Ref. 59043)
IUCN Red List Status (Ref. 124695)
Threat to humans
Fisheries: of no interest; aquarium: commercial; bait: occasionally
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01047 (0.00781 - 0.01405), b=3.11 (3.05 - 3.17), in cm total length, based on LWR estimates for this species (Ref. 93245
Trophic level (Ref. 69278
): 3.0 ±0.34 se; based on food items.
Generation time: 4.4 ( na - na) years. Estimated as median ln(3)/K based on 1 growth studies.
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (tm=2; tmax=5; Fec=40).
Vulnerability (Ref. 59153
): Moderate vulnerability (37 of 100) .