Environmental niche stability of Panstrongylus geniculatus (Hemiptera: Reduviidae) across historical and future climate scenarios

Panstrongylus geniculatus is one of the most widely distributed triatomine species in the Americas and an important vector of Trypanosoma cruzi, the causative agent of Chagas disease. This study evaluated changes in the environmental suitability of P. geniculatus under historical, current, and future climate scenarios across the Americas using ecological niche modeling. A total of 347 occurrence records and bioclimatic variables were used to calibrate ecological niche models in kuenm, which were subsequently projected to the Last Glacial Maximum, the current climate, and future conditions (2061–2080) under the RCP4.5 and RCP8.5 scenarios. Model projections indicated broad, relatively stable areas of environmental suitability throughout the Neotropical region, with localized contractions in central Brazil and expansions in northern Mexico, Argentina, and Uruguay. Comparisons among temporal scenarios showed limited changes in environmentally suitable areas, with expansion and contraction areas remaining below 4% of the modeled extent. These results suggest that the climatic niche of P. geniculatus has remained relatively stable across the evaluated historical and future scenarios. The persistence of environmentally suitable areas highlights the importance of maintaining long-term entomological surveillance and vector monitoring under changing climatic conditions.