Una cronología del género Thylamys (Didelphidae, Thylamyini), con énfasis en las formas que habitan Argentina

The genus Thylamys includes several species of small mouse opossums living predominantly in aridand semi-arid regions of South America. In Argentina, where the genus has more species, different species have been recognized (T. bruchi, T. citellus, T. pallidior, T. pulchellus, T. sponsorius, and T. venustus), but their taxonomy is still confusing. Here, I summarize what we know of the systematics and taxonomy of Thylamys in Argentina, including the main sources of controversy between species. I also provide a differential diagnosis for the species I recognize, a chresonymy, and current distribution maps. Finally, I describe the main issues that should be addressed to improve our understanding of the genus in Argentina.