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Recent molecular hypotheses suggest that some traditional suprageneric
taxa of Characiformes require revision, as they may not constitute
monophyletic groups. This is the case for the Bryconidae. Various studies
have proposed that this family (considered a subfamily by some authors)
may be composed of different genera. However, until now, no phylogenetic
study of all putative genera has been conducted. In the present study, we
analyzed 27 species (46 specimens) of all currently recognized genera of
the Bryconidae (ingroup) and 208 species representing all other families
and most genera of the Characiformes (outgroup). Five genes were
sequenced: 16SrRNA, Cytochrome b, recombination activating gene 1 and 2
and myosin heavy chain 6 cardiac muscle. The final matrix contained 4699
bp and was analyzed by maximum likelihood, maximum parsimony and Bayesian
analyses. The results show that the Bryconidae, composed of Brycon,
Chilobrycon, Henochilus and Salminus, is monophyletic and is the sister
group of Gasteropelecidae + Triportheidae. However, the genus Brycon is
polyphyletic. Fossil studies suggest that the family originated
approximately 33 million years ago (Ma) and that one of the two main
lineages persisted only in trans-Andean rivers, including Central American
rivers, suggesting a much older origin of Mesoamerican ichthyofauna than
previously accepted. Bryconidae is composed by five main clades, including
the genera Brycon, Chilobrycon, Henochilus and Salminus, but a taxonomic
review of these groups is needed. Our results points to a possible ancient
invasion of Central America, dating about 17.4+/-8 Ma (late Oligocene/late
Miocene), to explain the occurrence of Brycon in Central America.
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