Biologist graduated from the Federal University of Bahia (UFBA) and a master's student in the Graduate Program in Biodiversity and Evolution (PPGBioEvo/UFBA). Her academic experience focuses on fish bio-geography, with an emphasis on the analysis of phylogeographic and phylogenetic patterns. During her undergraduate studies, she worked at the Laboratory of Animal Systematic and Bio-geography (SIBA), contributing to research projects on the bio-geography and taxonomy of neotropical fish. She is currently studying the phylogeography of fish from the subfamily Cheirodontinae in four neotropical ecoregions, using comparative approaches to investigate their evolutionary history.

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Compsura is a genus of freshwater fish belonging to the order Characiformes and the family Characidae, subfamily Cheirodontinae. The type species, Compsura heterura, was described based on specimens from the Itapicuru river basin, which is part of the North Group (GN) within the Northeastern Mata Atlântica freshwater ecoregion (NMAF) ecoregion. In addition, the species has been recorded in other basins of the GN in the NMAF, such as the Sergipe, Vaza-Barris, and Real river basins, as well as in the São Francisco (SF) ecoregion. The sharing of C. heterura between the São Francisco river basin and some drainages of the NMAF supports a previously suggested historical relationship between these ecoregions. While the sharing of fish species between these ecoregions offers initial insights into the biogeographical history of their rivers, population-level studies are still scarce. Thus, the present study aimed to investigate, describe, and analyze the phylogeographic pattern of C. heterura in the NMAF and SF ecoregions, as well as to perform molecular dating to propose divergence times within species among populations. Sequences of the mitochondrial COI and nuclear MYH6 markers were used, and phylogenetic, phylogeographic, and demographic history analyses were performed. The topologies obtained revealed that different populations of C. heterura form a monophyletic group, but the samples from the ecoregions and river basins do not form clades. Divergence times between the populations of C. heterura were estimated to be between the late Miocene and Pleistocene, periods that coincide with paleoclimatic and geological events that shaped the hydrodynamics of South America. The AMOVA results indicated that the current isolation of the basins is the best explanatory scenario for the current distribution pattern of the lineages of this species, as has been evidenced for other freshwater fishes. The results suggest that the biogeographical history of C. heterura in the NMAF and SF ecoregions may reflect the complex interactions between vicariance processes, dispersion, and intermittent gene flow, shaped by a constantly changing landscape.

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