Data from: Systematic and historical biogeography of the Bryconidae (Ostariophysi: Characiformes) suggesting a new rearrangement of its genera and an old origin of Mesoamerican ichthyofauna

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.

近期的分子假说指出，脂鲤目（Characiformes）的部分传统超属分类群需要进行分类修订，因为它们可能并非单系群（monophyletic group）。Bryconidae科（Bryconidae）便是如此。多项研究提出，该科（部分学者将其归为亚科）可能包含多个不同的属。然而截至目前，尚未有针对所有假定属的系统发育研究。
本研究分析了Bryconidae科所有当前公认属的27个物种（共46份标本，作为内类群（ingroup）），以及脂鲤目其余所有科以及多数属的208个物种（作为外类群（outgroup））。本研究共测序了5个基因：16SrRNA、细胞色素b（Cytochrome b）、重组激活基因1和2（recombination activating gene 1 and 2）以及心肌肌球蛋白重链6（myosin heavy chain 6 cardiac muscle）。最终的矩阵包含4699个碱基对（bp），并通过最大似然法（maximum likelihood）、最大简约法（maximum parsimony）以及贝叶斯分析（Bayesian analyses）进行了分析。
结果显示，由Brycon属（Brycon）、Chilobrycon属（Chilobrycon）、Henochilus属（Henochilus）以及Salminus属（Salminus）构成的Bryconidae科为单系群，且与Gasteropelecidae科（Gasteropelecidae）+ Triportheidae科（Triportheidae）构成姊妹群（sister group）。但Brycon属（Brycon）为多系群（polyphyletic group）。
化石研究表明，该科起源于约3300万年前（Ma），且其两个主要演化支中的一支仅存活于跨安第斯河流域（包括中美洲河流），这表明中美洲鱼类区系（Mesoamerican ichthyofauna）的起源时间比此前所认为的更为久远。Bryconidae科包含5个主要支系（clade），涵盖Brycon属（Brycon）、Chilobrycon属（Chilobrycon）、Henochilus属（Henochilus）以及Salminus属（Salminus），但仍需对这些类群开展分类学修订。我们的研究结果表明，可能存在一次古老的中美洲入侵事件，其发生时间约为17.4±8 Ma（渐新世晚期/中新世晚期），这可解释Brycon属（Brycon）在中美洲的分布情况。