Abstract

Triatoma infestans (Klug 1834) is a Reduvideae Hemiptera, one of the main vectors of Trypanosoma cruzi, the Chagas decease agent in the American Continent. The post embryo pedicel development is studied. The pedicel is a part of the ovarioles not completely described in the literature in particular for embryo and post embryo development of telotrophic ovaries in Hemiptera Heteroptera insects. The histological and ultra-structure modifications of such ovariole components, already present at hatching time, have been followed for each nymph instar. Pedicel length growth has been measured in all instars. The secretory activity of the pedicel epithelium has been morphometrically analyzed, from the third instar up to the fifth. An assessment was also made with just molted adult female ovarioles. The present work revealed that pedicel differentiation and cell activity start in the third nymph instar. The secretion product that fills the pedicel lumen and accumulates step wisely in the oviduct is different from the one found at the adult. Some probable pedicel functions are considered.