ABSTRACT
Triatoma barberi Usinger is a widely recognized vector of the protozoa Trypanosoma cruzi. The determination of its presence in the rural houses is made by direct observation of adults, nymphs, exuviae or eggs. For this reason, egg structural characteristics could facilitate the differentiation and identification of species that inhabit such environments. In here, the morphologic characteristics of eggs of T. barberi are described and analyzed with special attention to the anterior pole of the egg. The structural analysis of eggs by scanning electron microscopy (SEM) showed the presence of a wide and rough chorion edge, which contain aeropyles and micropyles. A deep spermatic canal between the endochorion and exochorion, and a trabecular network in the interior were also observed. The operculum showed cells with irregular growth and undefined polygonal shape. Externally, the operculum cells forms two rings of projections that surround a single extension located to the center. The cellular projections resemble respiratory horns, although the presence of aeropyles was not observed. The chorion structural characteristics can help to identify and separate close species in the Triatominae subfamily.