Author: de Melo & Buckup, 2006
Remark: Hensel (1870) described <i>Tetragonopterus aeneus</i> as a new species from Porto Alegre, Southern Brazil, however, it is a junior homonym of that of Günther (1860) whose specimens were taken from Oaxaca, Mexico.  Steindachner later listed this as a synonym of <i>T. rutilus</i> Jenyns 1842, along with <i>T. obscurus</i> Hensel 1870. Later, Eigenmann (1921:293) listed <i>T. rutilus</i>, <i>T. aeneus</i> Günther and <i>T. aeneus</i> Hensel as junior synonyms of <i>A. fasciatus</i> Cuvier 1819.  The obvious homonymy was obscured when Eigenmann placed <i>T. aeneus</i> of Günther as synonym of <i>Astyanax fasciatus aeneus</i> and that of Hensel as synonym of <i>A. fasciatus fasciatus</i>.  Through most of the 20th century <i>T. aeneus</i> remained as synonym of <i>A. fasciatus</i> or has been treated as a species of uncertain status.  Some authors maintained the association between <i>T. obscurus</i> and <i>T. aeneus</i> Hensel, and used the former as the valid name.  F. de Melo and P. Buckup revalidated and redescribed <i>T. aeneus</i> Hensel to avoid homonymy, and gave the new name <i>Astyanax henseli</i> (Ref. 56653).