Actinopteri (ray-finned fishes) > Cyprinodontiformes
(Rivulines, killifishes and live bearers) > Rivulidae
(Rivulines) > Rivulinae
Etymology: Trigonectes: Greek, trygon = a sting ray + Greek, nekton = swimmer (Ref. 45335). More on author: Myers.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic; non-migratory; depth range - m (Ref. ), usually - m (Ref. ). Tropical; 0°C -
South America: Tocantins River basin, Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 12.0 cm TL male/unsexed; (Ref. 36579)
Morphology | Morphometrics
soft rays: 16 - 17. Diagnosed by having straight mouth cleft; smaller pelvic fin of the male (tip reaching to the base of the 5th anal ray); and the presence of a pale pink stripe along the ventral margin of the male caudal fin (Ref. 26656).
Bottom spawner, 2 months incubation. Is easy to maintain in the aquarium (Ref. 27139).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Costa, W.J.E.M., 1990. Systematics and distribution of the neotropical annual fish genus Trigonectes (Cyprinodontiformes, Rivulidae), with description of two new species. Ichthyol. Explor. Freshwat. 1(2):135-150. (Ref. 26656)
IUCN Red List Status (Ref. 124695)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5156 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.4 ±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) .