A new species of Astyanax (Ostariophysi: Characidae) from the headwaters of the arheic Río Sucuma, Catamarca, Northwestern Argentina

• Main Authors: Guillermo E. Terán, Cristina I. Butí, J. Marcos Mirande
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Ictiologia 2017-06-01
• Series: Neotropical Ichthyology
• Subjects: Characiformes; Especie críptica; Especie endémica; Filogenia; Sistema arreico
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000200209&lng=en&tlng=en

ABSTRACT A new species of Astyanax is described from the arheic system of Río Sucuma, in Catamarca, Northwestern Argentina. The new species is distinguished from its congeners by a combination of characters including the presence of a broad vertical humeral spot, absence of maxillary teeth, and absence of circuli in posterior field of scales. Furthermore, this species is distinguished by the orbital diameter, head length, branched anal-fin rays, perforated lateral-line scales, transverse scales, dentary teeth with abrupt decrease in size. This species is, to date, the single known fish endemic of Río Sucuma basin.