Astyanax, BAIRD & GIRARD, 1854

ASTYANAX BAIRD & GIRARD, 1854 View in CoL

Type species: Astyanax argentatus Baird & Girard, 1854 .

Junior synonyms : Anoptichthys Hubbs & Innes, 1936 (type species Anoptichthys Jordani Hubbs & Innes, 1936 View in CoL ). Astyanacinus Eigenmann, 1907 View in CoL (type species Tetragonopterus moorii Boulenger, 1892 View in CoL ). Bertoniolus Fowler, 1918 (type species Bertoniolus paraguayensis Fowler, 1918 View in CoL ). Bramocharax Gill & Bransford, 1877 View in CoL (type species Bramocharax bransfordii Gill, 1877 View in CoL ). Catemaco (subgenus of Bramocharax View in CoL ) Contreras-Balderas & Rivera-Teillery, 1985 (type species Bramocharax caballeroi Contreras-Balderas & Rivera-Teillery, 1985 View in CoL ). Poecilurichthys Gill, 1858 (type species Poecilurichthys brevoortii Gill, 1858 View in CoL ).

Diagnosis: A monophyletic Astyanax can be diagnosed from the remaining Stethaprioninae by the following combination of characters: laterosensorial pore anterior to dilatator fossa oriented lateroventrally, rhinosphenoid (when present) lacking a dorsal expansion between olfactory nerves, presence of circuli on posterior field of scales, presence of an anterior branch of the tubule for passage of blood vessels on lamellar portion of maxilla, naked caudal fin and a complete lateral line.

Synapomorphies: According to the present analysis, the synapomorphies of this clade are 14 from molecular data and two from morphology: cusps of second premaxillary row of teeth forming an anteriorly concave semicircle from ventral view (179:0) and reduced lateral urohyal bony expansions (305:1).

Astyanax View in CoL was recovered as monophyletic with this composition in most analyses, but it included ‘ Astyanax ’ dolinae in some of them. The obtained support for the monophyly of Astyanax View in CoL is poor, but the clade is stable with the exception of the occasional inclusion of A. dolinae . In the final hypothesis herein obtained, Astyanax View in CoL is composed of A. microlepis Eigenmann, 1913 View in CoL as the sister-group of two large clades, one of them (the Astyanax argentatus View in CoL clade) containing the type species of the genus and including the Central- and North-American species. The other clade was composed of the Astyanax bimaculatus (Linnaeus, 1758) View in CoL group and related species.

The Astyanax argentatus View in CoL clade is recovered as monophyletic under all explored conditions, as supported by 34 molecular synapomorphies. This clade includes the type species of Astyanax View in CoL and most of the trans-Andean species.

The Astyanax bimaculatus clade, supported by 14 molecular synapomorphies, includes all analysed species assigned to the Astyanax bimaculatus group. Also, it contains two members of the Astyanax orthodus group and Astyanax maximus (Steindachner, 1876) . The species with a horizontally ovate humeral spot are, in the final hypothesis, paraphyletic in terms of A. maximus , which is obtained as the sister-species of A. argyrimarginatus Garutti, 1999 . However, the position of A. maximus is variable among the different analytical conditions, resulting in the monophyly of the A. bimaculatus group in some analyses.