Triatoma infestans is the triatomine that presents the greatest
dispersion area in South America. However, it is not known whether the
original characteristics of this insect remained in its long dispersion
process. The purpose of this work was to study comparatively the external
male genitalia of insects from different populations of T.
infestans, two from Brazil (Minas Gerais and Bahia) and one from Bolivia
(Cochabamba Valley), and to investigate the correlation between the
morphological and behavioral variations. Differences were observed in one
of the structures of the external genitalia (endosoma process) that could
be used to characterize the insects from the three populations studied.