Ecological and physiological thermal niches to understand distribution of Chagas disease vectors in Latin America

DE LA VEGA, GERARDO JOSÉ; SCHILMAN, PABLO

MEDICAL AND VETERINARY ENTOMOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017

0269-283X

In order to assess how triatomines (Hemiptera, Reduviidae), Chagasdisease vectors, are distributed along Latin America, we analyzed therelationship between the ecological niche and the limits of the physiologicalthermal niche in seven species of triatomines. We combined twomethodological approaches: species distribution models, and physiologicaltolerances. First, we modeled the ecological niche and identified the mostimportant abiotic factor for their distribution. Then, thermal tolerance limitswere analyzed by measuring CTmax, CTmin, upper lethal temperature, and"chill-coma recovery time". Finally, we used phylogenetic independentcontrasts to analyze the link between limiting factors and the thermaltolerance range for the assessment of ecological hypotheses which providea different outlook for the geo-epidemiology of Chagas disease. Intriatomines, thermo-tolerance range increases with increasing latitudemainly due to better cold tolerances, suggesting an effect of thermalselection. In turn, physiological analyses show that species reachingsouthernmost areas have a higher thermo-tolerance than those withtropical distributions, denoting that thermo-tolerance is limiting thesouthern distribution. Understanding the latitudinal range along itsphysiological limits of disease vectors, may prove useful to test ecologicalhypotheses, and improve strategies and efficiency of vector control at thelocal and regional levels.