Abstract

By compiling all available occurrence information for the three species of Taurocerastinae (Frickius costulatus Germain, 1897, Frickius variolosus Germain, 1897, and Taurocerastes patagonicus Philippi, 1866), their realized and their world potential distributions were predicted to estimate the role played by dispersal limitations and contemporary environmental factors in explaining their extant distributions. Variables related to productivity seemed to have a higher explanatory capacity for the distribution and spatial segregation of each species. The realized and potential distribution estimates suggest that these species occupy all South American territory with environmentally suitable conditions and that the contemporary distribution of taurocerastine species can be basically conditioned by their geographical isolation within the cold and cold-temperate regions of South America. However, environmental factors would be comparatively more relevant in the case of the apterous species, T. patagonicus, due to the small potential world area with environmentally favorable conditions.