Ictiofauna dulceacuícola y estuarina de la cuenca del golfo de Paria, Venezuela: composición y relaciones biogeográficas con la cuenca del Orinoco

The Paria Gulf Basin ichthyofauna comprises 218 species arranged in 14 orders and 50 families. Among these, 155 species are considered strictly freshwater and 63 species are euryhaline. The most representative orders were Characiformes (67 sp.) and Siluriformes (59 sp.), followed by the Perciformes (52 sp.), Cyprinodontiformes (9 sp.) and a miscellany of ten more orders that contain the remaining species. The family Characidae with 45 species (21.3 %) was the most diverse followed by the families Cichlidae with 20 species (9.5 %) and Loricariidae with 17 species (8.1 %). A list of the species is presented including habits and river system distribution. Four endemic species, Bryconamericus yokiae , Creagrutus hysginus , Chaetostoma venezuelae and Farlowella venezuelensis was found. The analyses of faunal similarity showed that the Paria gulf basin ichthyofauna shares almost all the species with the Orinoco basin. On the other hand, the presence of at least four endemic species seem to indicate that the Paria gulf basin represents a noteworthy biogeographyic area with an own evolutionary history. These aspects and the role of the Orinoco river delta on the fish species dispersion are discussed.