The blind and colorless cave tetra of Mexico is a famous member of the genus, but its taxonomic position is disputed: Some recognize it as part of the Mexican tetra (A. mexicanus) and this is supported by phylogenetic evidence,[3][4][5][6][7] but others recognize the cave form as a separate species, A.

The generic name comes from Astyanax, a character in Greek mythology, who was the son of Hector of Troy; in homage to this, several specific epithets also refer to the Iliad.

The lack of comprehensive phylogenetic analyses dealing with this genus is hindering a thorough review and the relationships remain as indeterminate as the monophyly is doubtful.

The results of 2020 study using a combination of molecular and morphological data appeared to confirm that Astyanax is not monophyletic and suggested the creation of two new genera and the resurrection of Psalidodon.

[8] Although included in Astyanax by FishBase, phylogenetic evidence supports moving A. aurocaudatus back to the monotypic genus Carlastyanax.