Monte Desert (Argentina): insect biodiversity and natural areas

Monte is a warm shrub desert of Argentina, having particular biogeographical interest because it lies between the Neotropical and Antarctic regions. A preliminary list of some insect families shows a high proportion of endemic genera and species, supporting the hypothesis that it constitutes a natural area with its own biodiversity. The distribution of some insect species shows great concordance with the area occupied by the Monte Desert, indicating its limits. However the complete series of records are not enough to define the boundaries exactly. The distributional patterns of several endemic species suggest that within Monte there are five natural areas: Northern, Central, Uspallata-Calingasta, Southern, and Península de Valdés. The limits of the Northern and Uspallata-Calingasta areas are due to physiographical features (mountains) whereas the remaining areas are delimited by climatic barriers. An analysis based on phylogenetic information shows that these areas of endemism reflect different values with respect to their biodiversity. The Northern area has the highest values of importance and has no protected areas.