Some species of avian malaria parasites are invaders and responsible for diversity losses worldwide. Here we analyze the prevalence and genetic characterization of avian malaria and related haemosporidian parasites in Neotropical birds from two different regions of Peru. We detected an overall prevalence of 32.4 % comprising 12 infected bird species. The pathogen Plasmodium relictum SGS1 was widespread and the most prevalent parasite found in our study (39 % of the total infections), infecting 8 host species in both localities. To the best of our knowledge, this is the first report of this invasive pathogen in the mainland Americas, thus representing a possible menace to over one-third of all bird species in the world.