Morphological changes associated with brachypterous Triatoma guasayana (Hemiptera, Reduviidae) and their relationship with flight

Abstract

Flight is the main form of dispersion for adult triatomines. It is postulated here that some body morphological parameters vary in T. guasayana according to a greater or lesser wing development, which would allow to estimate their flight capacity. Furthermore, there are observations which allow to suggest that the wings alone would not present the entirety of the information on the flight ability of an insects. It is postulated here that some body morphological parameters vary in T.guasayana according to a greater or lesser wing development. The study aims to verify the hypothesis that the variation of the wing phenotype in triatomines is accompanied by variations of other body structures, particularly the head. Geometric morphometry of heads, thorax width and wing length of T.guasayana brachypterous and macropterous was used. The results allow to confirm that there is a relationship between the wing condition of T. guasayana and other variables – unrelated to wings – that can be associated with flight capacity. The shape of the head changes with the wing condition. The results obtained suggest that the diversity of wing morphotypes imply a diversity in head conformation, suitable for flight: macropterous have a greater distance between eyes and shorter heads, while brachy or micropterous exhibit smaller eyes and larger heads. For the first time, brachypterous individuals of T.guasayana are recorded here, posing the existence of a pronounced alary polymorphism in this species. Identifying these markers in triatomines is of special importance to understand the processes of domicile recolonization after vector control campaigns.