Mepraia parapatrica is one of the lesser known and less abundant sylvatic triatomine species naturally infected by the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. M. parapatrica lives in sympatry with T. cruzi-infected rodents, but only birds, reptiles, and marine mammals have been reported as blood-meal sources of this vector species by serology. The distribution range of this kissing bug overlaps with fishers’ settlements and tourist areas, and therefore the study of the blood-meal sources of this triatomine species is relevant. Here, we determined the blood-meal sources of M. parapatrica by NGS or standard sequencing from a coastal mainland area and an island in northern Chile, and T. cruzi infection by real-time PCR. The blood-meals of. M parapatrica included 61.3% reptiles, 35.5% mammals (including humans) and 3.2% birds. Feeding on reptiles was more frequent on the mainland, while on the island feeding on mammals was more frequent. The presence of T. cruzi-infected triatomine bugs and humans as part of the diet of M. parapatrica in both areas represents an epidemiological threat and potential risk to the human population visiting or established in these areas. Currently there are no tools to control wild triatomines; these results highlight the potential risk of inhabiting these areas and the necessity of developing information campaigns for the community and surveillance actions.

Organisms in adaptive radiations are able to diversify and colonize multiple environments. Frequently, the evolution of key adaptations enables organisms to confront novel environmental challenges, promoting diversification. Here, we studied desert colonization in the Liolaemus radiation. We assessed the patterns of climatic niche evolution in the L. nigromaculatus section, one Liolaemus clade inhabiting the Atacama Desert. We found that evolution toward arid conditions occurred in two clades independently: one clade colonized the desert through warm coastal environments, and the other through cold highland environments on the Andes Mountains. The precipitation climatic niche evolved fast and early during this clade’s evolutionary history, following an early burst (EB) model of evolution, whereas the thermal climatic niche evolved under Brownian motion (BM) and at a lower rate. Additionally, we explored some features that could have facilitated desert colonization: a higher chromosome number was associated with warmer temperatures, lower selected body temperatures were associated with higher environmental temperatures and drier climates, larger and more elongated bodies with colder environments, and longer limbs and tails were associated with higher thermal variation. Our results highlight that organisms can confront challenging environments in multiple ways such that some niche axes may evolve faster during the colonization of novel environments, and that radiated groups may have the evolutionary potential to rapidly evolve these adaptations.