Ecogenetics of Triatoma sordida and Triatoma guasayana (Hemiptera : Reduviidae) in the Bolivian Chaco
Résumé
#Triatoma guasayana$ and two putative cryptic species pertaining to #T. sordida$ complex (named groups 1 and 2) occur in sympatry in the Bolivian Chaco. Using multilocus enzyme electrophoresis and subsequent genetic analysis, our work assesses their population distribution and dispersal capacity in domestic, peridomestic, and silvatic environments. Our collections by light trap in the silvatic environment indicated a predominance of #T. guasayana$ and #T. sordida$ group 2 and a lesser abundance of #T. sordida$ group 1 (less than or equal to 10% of the total of captures). Their similar distribution in two silvatic areas 80 km apart supports the hypothesis of their homogeneous dispersal through the Bolivian Chaco. The distribution of #T. guasayana$ and #T. sordida$ groups 1 and 2 was similar between silvatic environment and peridomestic ecotopes where 25% of positive places were occupied by two or three species. Bromeliads were confirmed as favorable shelter for #T. guasayana$ but were free of #T. sordida$. #T. sordida$ group 1 and to a lesser extent #T. guasayana$ would be more invasive vectors for houses than #T. sordida$ group 2. The spatial partition in the three species sampled in two distant sites suggested a reduced dispersive capacity. (Résumé d'auteur)