The eggshells of Sergentomyia minuta, S. schwetzi and S. ingrami are studied by scanning (SEM) and transmission (TEM) electron microscopy. In all three species the surface sculpturing is characterized by a polygonal pattern due to intersecting ridges. Each ridge is formed by columns arranged in palisade and resting on a reticular basal layer. TEM shows that the columns represent the outer chorion and the basal layer the intermediated one. Under these layers an inner chorion and a vitelline envelope are present. The eggshell structures of the three species are compared with those of other Phlebotominae and their taxonomic value is discussed.
