Actinopteri (ray-finned fishes) > Characiformes
(Characins) > Characidae
(Characins; tetras) > Tetragonopterinae
Etymology: Tetragonopterus: Name from Greek words: 'Tetra' meaning four; 'gonia' meaning angle; 'pteron' for fin; referring to the evident tetragonal shape of the body (Ref. 124043). More on author: Cuvier.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; pelagic; pH range: 5.8 - 8.5; dH range: ? - 30; depth range - m (Ref. ), usually - m (Ref. ). Tropical; 22°C - 27°C (Ref. 1672)
South America: Amazon basin, upper Essequibo, Orinoco, Parnaíba, Jaguaribe, Paraguay and lower Paraná river basins.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 11.2 cm SL male/unsexed; (Ref. 79891)
Morphology | Morphometrics
soft rays: 28 - 40;
Vertebrae: 27. This species is distinguished from all its congeners by the following characters: predorsal scales 11-17 (vs. 7-9); differs from T. anostomus, T. denticulatus, T. kuluene, T. juruena by the principal teeth in dentary 4 (vs. 5-6), and larger and more robust teeth (vs. thinner and sharper); differs from T. anostomus, T. araguaiensis by the number of gill-rakers on the upper limb of the first gill arch 12-15 (vs.17-20); differs from T. anostomus by having a terminal mouth (vs. subsuperior mouth); differs from T. ommatus the maxillary teeth 1-4 (vs. 7-8) and by the presence of a conspicuous dark mark on the caudal peduncle (vs. inconspicuous mark limited to the posterior portion of the caudal peduncle); differs from T. carvalhoi by having a rounded dark mark on the caudal peduncle (vs. lozenge-shaped dark mark on the caudal peduncle); differs from T. rarus by the absence of dark longitudinal stripes on the trunk (vs. presence of such stripes); differs from T. rarus, T. georgiae having the scale rows between lateral line and pelvic-fin origin 3.5 (vs. 4.5-5.5); differs from T. denticulatus by having humeral marks separated by one or two vertical rows of scales (vs. humeral marks separated by three vertical scale rows) (Ref. 124043).
Consumed locally for recovery or during illness. Carnivorous (Ref. 42843).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Is being bred in Asia and Florida in ponds (Ref. 1672).
Silva, G.S.C., B.F. Melo, C. Oliveira and R.C. Benine, 2016. Revision of the South American genus Tetragonopterus Cuvier, 1816 (Teleostei: Characidae) with description of four new species. Zootaxa 4200 (1):1-46. (Ref. 124043)
IUCN Red List Status (Ref. 124695)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5020 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.02188 (0.00852 - 0.05619), b=3.00 (2.78 - 3.22), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.2 ±0.4 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .