| Summary: | The order Osteoglossiformes represent one of the most basal groups among the Teleosteos. These fishes live exclusively on freshwater environments and are characterized by the presence of a bonytongue. The group is a good model for evolutive studies due the presence of alive representatives in all continental lands localized on south hemisphere (except the Antarctic continent) even with a gondwanica origin (allowing to perform inferences about vicariant/dispersal events). The members of the Notopteridae family are distributed throughout the African and Asian (in tropical region) continents. In order to explain the distribution of the Asian biota that has close relations with the species present in Africa, the hypothesis "Out-of-India" was proposed. The idea in this hypothesis is that the lineages previously present in Gondwana reached Asia through the continental drift of the Indian subcontinent. This idea was considered the better explanation for the distribution of notopterids during a long time, but recent molecular data disclose disagreements between the geological times of tectonic drift and molecular divergence. In this context, we perform chromosomal and molecular approaches to infer about the group's diversity in relation to its biogeography. Chromosomal approaches involved classical banding techniques as well as FISH assays using repetitive DNA probes, chromosome painting and CGH; while the molecular approach was performed through the analysis of allelic sequences containing SNP polymorphisms obtained by the DArTseq genotyping technique, which involves next generation sequencing technology. The results of cytogenetic data pointed a diploid number variation in two of the seven species here studied, and also was verified variations for the distribution of the rDNA 18S and rDNA 5S markers for three species. This variation for the karyotype structure in the family was better evidenced by the CGH results, in which few chromosomal segments were shared between the intergeneric crossings assays. Indeed, these ...
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