Biogeografia histórica de Anablepidae (Teleostei: Cyprinodontiformes) : inferências com métodos pan-biogeográfico e cladístico.

Abstract

Knowledge on hydrological evolution of the Neotropical region was used along with the current phylogeny and distribution of Anablepidae species to investigate questions about the historical biogeography of the family, such as the delimitation of areas of endemism, ancestral ranges of the current Anablepidae clades and probable vicariant and dispersionist events which determined the present geographical distribution of the family. Areas of endemism were delimited by Parsimony Analysis of Endemicity (PAE) using 73 grid cells of 2° latitude by 2 ° longitude. Statistical Dispersal-Vicariance Analysis (S-DIVA) was used to reconstruct possible ancestral ranges and to detect the historical events associated to the evolution of the family species based on their phylogeny (Oxyzygonectes (Anableps + Jenynsia [(Jenynsia) + (Plesiojenynsia)])). In the strict consensus cladogram of PAE, three clades were supported by two species and were then interpreted as areas of endemism. These areas correspond to localities near the Andean foothills, Iguaçu River basin, and Atlantic drainages in the north of South America. S-DIVA suggested that the common ancestral of the family was widely distributed in areas currently undergoing Pacific drainages in Central America, Atlantic drainages in the north and southeast of South America and Lower Paraná. A dispersal event was responsible for the isolation of Oxyzygonectes, a vicariant event by the separation of Anableps and Jenynsia and two other vicariances occurred within Anableps and in the separation of Plesiojenynsia and Jenynsia subgenera. There is strong evidence that the Jenynsia and Plesiojenynsia species are marine derived lineages. We postulate the existence of centers of diversification to the family in the areas of endemism and an intimate association with the ecological processes and historical events that occurred in the paleogeological and paleogeographic evolution of the Neotropical region, especially to the episodes of oscillations of the ocean level from middle Miocene to Pleistocene.