Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Characiformes
(Characins) > Characidae
(Characins) > Stevardiinae
Etymology: obi: Named from a Guaraní word obi, meaning blue, in allusion to the ground color of the body.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Subtropical
South America: tributaries of the río Paraná basin in Argentina.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 5.9 cm SL male/unsexed; (Ref. 91033)
Morphology | Morphometrics
Vertebrae: 37. Distinguished by the following combination of characters: anal fin with 22-24 (mode=24) branched rays; body depth at dorsal-fin origin 34.5-40.8 % SL (mean=37.9 % SL); nearly straight distal border of anal fin in matures males; and lateral line interrupted or with alternated series of perforated and non perforated scales. Other characters useful to diagnose this species include the following: 7-14 sheath scales on anal-fin base; anal-fin base length 2.9-3.4 in SL; interorbital width 2.7-2.9 in HL; 34-38 scales on longitudinal series; horizontal eye diameter 35.9-42.1% SL; snout length 24.0-27.3 % HL; upper jaw length 42.0-46.9% HL; maxillary teeth 3-6; pelvic-fin length 14.5-18.1% SL; snout to pelvic-fin origin 44.4-50.6% SL; snout to anal-fin origin 59.4-65.3% SL; snout to pelvic-fin origin 44.4-50.6% SL (Ref. 91033).
The localities where the species were found had a turbid and rapidly flowing water
after heavy rain. The bottom is composed of mud, sand and stones (Ref. 91033).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Casciotta, J., A. Almirón, L. Piálek and O. ?í?an, 2012. Cyanocharax obi, a new species (Characiformes: Characidae) and the first record of the genus from tributaries of the río Paraná basin, Argentina. Zootaxa 3391:39-51. (Ref. 91033)
IUCN Red List Status (Ref. 115185)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5039 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01175 (0.00533 - 0.02588), b=2.98 (2.78 - 3.18), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.0 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .