“…Lizaraso (1957) concluded that populations of the same species, when provided with different laboratory and natural environments, could produce variations that affected the dimensions of the eggs without affecting the characteristics of the chorion, which remained constant. Morphometric studies of 33 Triatoma species were published (Galliard 1935b, Lizaraso 1957, Gonçalves et al 1985, Haridass 1986, Jurberg et al 1986, 1998, Jurberg & Vogel 1994, Jurberg & Campos 1995, Rosa 1995, Rocha et al 1996, Costa et al 1997, Silva et al 2000, Visciarelli et al 2004, Obara et al 2007a). According to Barata (1998), Triatoma possesses the following means: length, 2.05 ± 0.08 and diameter, 1.14 ± 0.05.…”