Leptagoniates

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Superclassis/Classis: Actinopterygii
Classis/Subclassis: Actinopteri
Subclassis/Infraclassis: Neopterygii
Infraclassis: Teleostei
Megacohors: Osteoglossocephalai
Supercohors: Clupeocephala
Cohors: Otomorpha
Subcohors: Ostariophysi
Sectio: Otophysa
Ordo: Characiformes

Familia: Characidae
Subfamilia: Aphyocharacinae
Genus: Leptagoniates
Species: L. steindachneri

Note: Acc. to Tagliacollo et al. (2012), Leptagoniates pi Vari, 1978 is not closely related to either the type species of ths genus or to the subfamily Aphyocharacinae.
Name

Leptagoniates Boulenger, 1887

Type species: Leptagoniates steindachneri Boulenger, 1887
References

Boulenger, G. A., 1887: An account of the fishes collected by Mr. C. Buckley in eastern Ecuador. Proceedings of the Zoological Society of London, 1887 (2): 274–283, Pls. 20-24.
Tagliacollo, V. A., Souza-Lima, R., Benine, R. C. & Oliveira, C., 2012: Molecular phylogeny of Aphyocharacinae (Characiformes, Characidae) with morphological diagnoses for the subfamily and recognized genera. Molecular Phylogenetics and Evolution, 64: 297–307.

Leptagoniates is a genus of fish in the family Characidae. It contains the single species Leptagoniates steindachneri,[1] which is found in the Amazon River basin in South America.

Another species, L. pi, has traditionally been placed in this genus, but it was moved to Protocheirodon in 2016.[1]
References

Vari, R.P., Melo, B.F. & Oliveira, C. (2016): Protocheirodon, a new genus of Characidae (Teleostei: Characiformes) with the redescription of the poorly known Protocheirodon pi. Neotropical Ichthyology, 14 (2): e150154.`