Interaction between two aggregation chemical signals in Triatoma infestans (Hemiptera: Reduviidae)

The nymphs and adults of Triatoma infestans spend much of their time aggregated among themselves within narrow and dark shelters. The search for a suitable shelter depends in part on the recognition of chemical signals coming from the feces and the cuticle of the other individuals who use the refuge. The aim of this study was determine the possible interaction between the chemical signals associated to the feces and to the cuticle of T. infestans. The results showed that the insects remained significantly more time on the feces that had contact with legs and the feces plus footprints than feces or footprints alone, demonstrating the interaction between evaluated signals. These results demonstrates also that feces extracted a chemical stimulus from the legs. Understanding the interaction feces-legs as an interaction feces-cuticle of legs, the results suggest that the feces could extract some cuticular compound with activity on the behavior of the insects. This is the first report of the interaction between the two aggregation signals recognized in T. infestans and of the increase in the behavioral response of insects exposed to feces that had contact with a cuticular structure.