A species of tetra has been moved to a new genus and given a new species name.
Tetragonopterus aeneus, which was originally described by Hensel in 1870, was brought out of synonymy by Filipe de Melo and Paulo Buckup and has had to been renamed Astyanax henseli to avoid confusion with another fish already called Astyanax aeneus.
Their paper in the latest issue of the journal Neotropical Ichthyology explains that the fish Hensel described as T. aeneus has been considered as a synonym of various other species over the years.
Just six years after Hensel first described the species, Steindachner said that the species, along with T. obscurus, was a synonym of T. rutilus.
In 1910, Eigenmann, who undertook extensive studies of the fishes of South America, moved the majority of the members of the Tetragonopterus genus to Astyanax.
Among the fishes moved to Astyanax by Eigenmann was a different species of fish called Tetragonopterus aeneus that was described by Gunther in 1860.
Because de Melo and Buckup found that Hensel's Tetragonopterus aeneus was actually a distinct species, and not a synonym of another fish, they had to give it a new name to prevent a homonym clash occurring with two species both bearing the name Astyanax aeneus.
For more details see the paper: FAG de Melo and PA Buckup (2006) - Astyanax henseli, a new name for Tetragonopterus aeneus Hensel, 1870
from southern Brazil (Teleostei: Characiformes). Neotropical Ichthyology, 4(1):45-52, 2006.
Astyanax species distributionsThe members of the Astyanax genus are quite widespread through South and Central America and the genus currently contains around 90 valid species. You can view the distributions of some of these fishes on Practical Fishkeeping's Fish Mapper application.
Astyanax abramis
Astyanax alburnus
Astyanax altiparanae
Astyanax angustifrons
Astyanax anterior
Astyanax argyrimarginatus
Astyanax armandoi
Astyanax asuncionensis
Astyanax atratoensis
Astyanax bimaculatus
Astyanax bourgeti
Astyanax brachypterygium
Astyanax brevirhinus
Astyanax caucanus
Astyanax chaparae
Astyanax cordovae
Astyanax correntinus
Astyanax cremnobates
Astyanax daguae
Astyanax depressirostris
Astyanax eigenmanniorum
Astyanax erythropterus
Astyanax fasciatus
Astyanax fasslii
Astyanax festae
Astyanax filiferus
Astyanax gisleni
Astyanax giton
Astyanax goyacensis
Astyanax gracilior
Astyanax guaporensis
Astyanax guianensis
Astyanax gymnogenys
Astyanax hastatus
Astyanax integer
Astyanax intermedius
Astyanax ita
Astyanax jacuhiensis
Astyanax janeiroensis
Astyanax jenynsii
Astyanax jordani
Astyanax kennedyi
Astyanax kompi
Astyanax kullanderi
Astyanax latens
Astyanax laticeps
Astyanax leonidas
Astyanax leopoldi
Astyanax lineatus
Astyanax longior
Astyanax maculisquamis
Astyanax magdalenae
Astyanax marionae
Astyanax maximus
Astyanax megaspilura
Astyanax mexicanus
Astyanax microlepis
Astyanax multidens
Astyanax mutator
Astyanax myersi
Astyanax nasutus
Astyanax nicaraguensis
Astyanax obscurus
Astyanax ojiara
Astyanax orbignyanus
Astyanax orthodus
Astyanax paraguayensis
Astyanax parahybae
Astyanax paranahybae
Astyanax paris
Astyanax pelegrini
Astyanax poetzschkei
Astyanax pynandi
Astyanax ribeirae
Astyanax robustus
Astyanax ruberrimus
Astyanax saguazu
Astyanax saltor
Astyanax scabripinnis
Astyanax schubarti
Astyanax scintillans
Astyanax stenohalinus
Astyanax stilbe
Astyanax superbus
Astyanax symmetricus
Astyanax taeniatus
Astyanax trierythropterus
Astyanax troya
Astyanax turmalinensis
Astyanax unitaeniatus
Astyanax validus
Astyanax venezuelae
Astyanax villwocki