Chemotaxonomy of Five South American Species of the Triatoma genus (Hemiptera: Reduviidae: Triatominae) Based on Their Cuticle Hydrocarbon Pattern

Abstract

The Triatoma sordida subcomplex traditionally included four triatomine species, T. sordida, Triatomagarciabesi, Triatoma guasayana, and Triatoma patagonica, distributed in the Southern Cone of South America.These species have a large intraspecific variability together with an overall similarity, making difficult to establish their taxonomic status. Many cytogenetic, morphometric, and molecular markers have been appliedto address this. Recent studies have posed concerns on the inclusion of T. guasayana and T. patagonica withinthe subcomplex. Also, T. sordida from Argentina has been designed as a new species, Triatoma rosai. Usingthe cuticular hydrocarbon pattern as chemotaxonomic marker, the relationships among several populationsof these species were analyzed by capillary gas chromatography and linear discriminant analysis along 25collection sites in Argentina, Bolivia, Brazil, and Paraguay. T. sordida and T. rosai populations were differentially clustered in two CHC-based groups: ?Group 1? included T. sordida from Eastern Brazil, Eastern Paraguay,and the Bolivian populations from La Paz and Izozog G1; ?Group 2? included T. rosai, and T. sordida fromIzozog G2 (Bolivia), and Western Paraguay. Whereas T. garciabesi remained closely related to T. sordida andT. rosai, T. guasayana, and T. patagonica were clearly separated from the species of the T. sordida subcomplex.Our results agree with those from other several techniques suggesting that the taxonomy of the T. sordidasubcomplex should be revised.