Abstract. The phylogenetic position of Triatoma sherlocki within triatomines group was inferred by analyzing mtDNA fragments of Cyt B and 16S ribosomal RNA by using maximum parsimony and Bayesian analysis. Despite being differentiated from members of the T. brasiliensis complex on morphologic grounds, molecular phylogenetic analysis suggests T. sherlocki is a member of this complex; moreover, it was placed as a sister species of T. melanica . These suggestions were supported by robust credibility rates. Hence, we show evidence for the paraphyletic group of the " Triatoma brasiliensis complex," which should be composed of T. brasiliensis brasiliensis , T. brasiliensis macromelasoma , T. juazeirensis , T. melanica , and T. sherlocki .

The phylogenetic relationships among species of Triatoma matogrossensis subcomplex ( T. baratai, T. guazu, T. matogrossensis, T. sordida, T. vandae, and T. williami) was addressed by using fragments of cytochrome oxidase I (COI), 16S rDNA (16S), and cytochrome b (Cytb) through Bayesian and parsimony analyses. We did not recover a monophyletic T. matogrossensis subcomplex, and their members were found clustered in three strongly supported clades, as follows: i) T. jurbergi + T. matogrossensis + T. vandae + T. garciabesi + T. sordida; ii) with T. guasayana as the sister group of clade (i); and iii) T. williami + T. guazu, however not closely related to the clade formed by the previously mentioned species. The other two endemic species from Central-Western Brazil, T. baratai and T. costalimai, were not recovered with strong clade support as related to other members of this subcomplex. Results call for a further revision in the classification of the subcomplexes within the genus Triatoma.