Triportheus

Triportheus
Triportheus angulatus
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Division: Teleostei
Order: Characiformes
Family: Triportheidae
Subfamily: Triportheinae
Fowler, 1940
Genus: Triportheus
Cope, 1872[1]
Type species
Triportheus albus
Cope, 1872[1]
Synonyms[1]

Triportheus is a genus of freshwater ray-finned fishes belonging to the family Triportheidae, the hatchet characins or keeled characins. The fishes in this genus are found in South America, including Trinidad, ranging from the Rio de la Plata basin to the basins of the Orinoco and Magdalena.[2][3] Some are migratory.[2] This genus is classified in the subfamily Triportheinae.[4]

The largest species is up to 36 cm (14 in) in standard length, but most reach up to about 2⁄3 of that size or less.[3] They somewhat resemble larger, more elongated hatchetfish, including a keeled chest and large pectoral fins.[2] This leads to the common names narrow hatchetfish and elongate hatchetfish, the latter also used more specifically for T. elongatus. Their shape is an adaption for living near the water surface where they find most of their food such as fruits, seeds, leaves, flowers, other plant material, invertebrates (insects, spiders and alike) and occasionally small fish.[2] Seeds eaten by Triportheus are sometimes crushed, but may also pass undamaged through the fish, making them potential seed dispersers.[2]

Some Triportheus species are habitat generalists: T. albus is found in blackwater, whitewater, and clearwater rivers.[5][6] Fish of this genus are r-strategists, maturing quickly and having a relatively short lifespan; within the Solimões River floodplain, the native Triportheus were noted to have high natural mortality.[7] Larvae inhabit open water, while older individuals (postflexion and juvenile stages) shelter under macrophytes and within the shallows or marginal regions of the waterbody.[8]

Triportheus are exploited commercially in their native range, and some species may be at risk for overfishing.[7] In their native range, multiple species are referred to as sardinas, though there are many other local names.[9]

Species

Striated heron eating a Triportheus

The genus encompasses the following species,[10] with the following distributions:[11]

  • Triportheus albus Cope, 1872 (Amazon, Araguaia, and Tocantins basin)
  • Triportheus angulatus (Spix & Agassiz, 1829) (Amazon basin)
  • Triportheus auritus (Valenciennes, 1850) (Amazon, Araguaia, Tocantins, Orinoco basin and North Coastal drainages)
  • Triportheus brachipomus (Valenciennes, 1850) (Orinoco basin and North Coastal drainages)
  • Triportheus claudiae Lopes & Carvalho, 2024[12]
  • Triportheus culter (Cope, 1872) (Amazon basin)
  • Triportheus curtus (Garman, 1890)
  • Triportheus guentheri (Garman, 1890) (Sao Francisco basin)
  • Triportheus magdalenae (Steindachner, 1878) (Magdalena basin)
  • Triportheus nematurus (Kner, 1858) (Paraguay and lower Paraná Basin)
  • Triportheus orinocensis {M. C. S. L. Malabarba, 2004
  • Triportheus pantanensis M. C. S. L. Malabarba, 2004 (Paraguay and lower Paraná Basin)
  • Triportheus pictus (Garman, 1890)
  • Triportheus rotundatus (Jardine, 1841) (Amazon basin)
  • Triportheus signatus (Garman, 1890) (Parnaíba Basin)
  • Triportheus trifurcatus (Castelnau, 1855) (Araguaia and Tocantins basin)
  • Triportheus venezuelensis M. C. S. L. Malabarba, 2004 (Orinoco basin and North Coastal drainages)

The following cladogram is based on a time-calibrated phylogenetic tree using genetics:[11]

Triportheus

Triportheus pantanensis

Triportheus angulatus

Triportheus trifurcatus

Triportheus sp. nov. (Lagoa Margina/Rio Xingu/Canarana)

Triportheus signatus

Triportheus venezuelensis

Triportheus orinocensis

Triportheus nematurus

Triportheus aff. rotundatus

Triportheus brachipomus

Triportheus albus

Triportheus guentheri

Triportheus magdalenae

Triportheus culter

Triportheus rotundatus

Triportheus auritus

Lignobrycon

Bryconidae

Gasteropelecidae

References

  1. 1 2 3 Fricke, Ron; Eschmeyer, William N. & van der Laan, Richard (eds.). "Genera in the family Triportheinae". Catalog of Fishes. California Academy of Sciences. Retrieved 13 August 2025.
  2. 1 2 3 4 5 Goulding, M (1980). The Fishes and the Forest: Explorations in Amazonian Natural History. University of California Press. pp. 131–152. ISBN 0-520-04131-3.
  3. 1 2 Froese, Rainer; Pauly, Daniel (eds.). "Species in genus Triportheus". FishBase. October 2017 version.
  4. ↑ Fricke, Ron; Eschmeyer, William N. & van der Laan, Richard (eds.). "Genera in the family Triportheidae". Catalog of Fishes. California Academy of Sciences. Retrieved 2 Jun 2025.
  5. ↑ Hay, Abbie C.; Sandoval-Castillo, Jonathan; Cooke, Georgina M.; Chao, Ning L.; Beheregaray, Luciano B. (4 March 2022). "Riverscape Genomics Clarifies Neutral and Adaptive Evolution in an Amazonian Characin Fish (Triportheus albus)". Frontiers in Ecology and Evolution. 10 825406. Bibcode:2022FrEEv..1025406H. doi:10.3389/fevo.2022.825406.
  6. ↑ Araújo, José D. A.; Ghelfi, Andrea; Val, Adalberto L. (31 August 2017). "Triportheus albus Cope, 1872 in the Blackwater, Clearwater, and Whitewater of the Amazon: A Case of Phenotypic Plasticity?". Frontiers in Genetics. 8 114. doi:10.3389/fgene.2017.00114. PMC 5583242. PMID 28912799.
  7. 1 2 Salomão, Clara Brito; Gonçalves, Vitor Dalmacio; Soares, Jessyana Maria de Sousa; Oliveira, Marcos Sidney Brito; Soares, Maria Gercilia Mota; Prestes, Luiza (21 August 2023). "Stock assessment and population parameters for Triportheus spp. and Pellona flavipinnis in floodplain lakes, central of Amazon, Brazil". Boletim do Instituto de Pesca. 49. doi:10.20950/1678-2305/bip.2023.49.e723. Retrieved 7 August 2026.
  8. ↑ "Open-access Early life history of two Neotropical Triportheidae fish (Characiformes)". Neotropical Ichthyology. 21 (1). 7 March 2023. doi:10.1590/1982-0224-2022-0102.
  9. ↑ "Sardinhas". Amazon Waters Alliance. Retrieved 8 August 2026.
  10. ↑ Fricke, Ron; Eschmeyer, William N. & van der Laan, Richard (eds.). "Species in the genus Triportheus". Catalog of Fishes. California Academy of Sciences. Retrieved 13 August 2025.
  11. 1 2 Mariguela, T.C.; Roxo, F.F.; Foresti, F.; Oliveira, C. (March 2016). "Phylogeny and biogeography of Triportheidae (Teleostei: Characiformes) based on molecular data". Molecular Phylogenetics and Evolution. 96: 130–139. Bibcode:2016MolPE..96..130M. doi:10.1016/j.ympev.2015.11.018. hdl:11449/168270. PMID 26721557.
  12. ↑ Lopes, Douglas Alves; Carvalho, Fernando Rogério (July 2024). "Taxonomy of Triportheus (Ostariophysi: Triportheidae) from the Paraná-Paraguai basin, South America". Neotropical Ichthyology. 22 (2) e230121. doi:10.1590/1982-0224-2023-0121.