Highlighting Astyanax Species Diversity through DNA Barcoding

MIRANDA OLIVEIRA, C.A.; DÍAZ DE ASTARLOA, J. M.; OLIVEIRA C.; ROSSINI, B.; GONCALVES DE MELO, F. A.; ARAUJO BERTACO V.; ROSSO, J.J.; FORESTI, F.

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2016 vol. 11 p. 1 - 20

1932-6203

DNA barcoding has been used extensively to solve taxonomic questions and identify newspecies. Neotropical fishes are found in a wide variety of shapes and sizes, with a largenumber of species yet to be described, many of which are very difficult to identify. Characidaeis the most species-rich family of the Characiformes, and many of its genera areaffected by taxonomic uncertainties, including the widely-distributed, species-rich genusAstyanax. In this study, we present an extensive analysis of Astyanax covering almost itsentire area of occurrence, based on DNA barcoding. The use of different approaches(ABGD, GMYC and BIN) to the clustering of the sequences revealed ample consistency inthe results obtained by the initial cutoff value of 2% divergence for putative species in theNeighbor-Joining analysis using the Kimura-2-parameter model. The results indicate theexistence of five Astyanax lineages. Some groups, such as that composed by the trans-Andean forms, are mostly composed of well-defined species, and in others a number ofnominal species are clustered together, hampering the delimitation of species, which inmany cases proved impossible. The results confirm the extreme complexity of the systematicsof the genus Astyanax and show that DNA barcoding can be an useful tool to addressthese complexes questions.