Distributional pattern of Characiforms in Chacoan Sub-region, Neotropical Region (sensu Morrone, 2014)

Abstract

Geographically, the greatest diversity of freshwater bony fish occurs in the Neotropical Region. Despite the richness of the neotropical ichthyofauna, studies about its origin and history are scarce. Overall, the recognized biogeographic patterns of freshwater fish are used only to complement patterns found in terrestrial taxa or are used to generate models to explain global biogeographic patterns. Furthermore, in general, biogeographical studies accomplished with fishes exclude biological aspects. Although the history of neotropical rivers and lakes is recent from the geochronological point of view, they have unique biotic complexities, which include an outstanding ichthyological diversity. In order to reconstruct and to understand the history of isolation, divergence and diversification of ichthyofauna, different tools of Historical Biogeography can be used, specifically Panbiogeography. This method emphasizes the geographic spatial dimension of biodiversity, allowing a better understanding of evolutionary patterns and processes. Through Panbiogeographical Track Analysis, it is possible to relate the geological history of a region to the distribution of specific or supraspecific taxa today. The aim of this study was to recognize distributional patterns of freshwater bony fish, specifically Characiforms, from Chacoan Sub-region. As a result, there are 16 generalized tracks and one node. Characiform families share distributional patterns with other taxa. These patterns are congruent with the geological history of the Chacoan Subregion.