Effect of sequential heat and cold shocks on nuclear phenotypes of the blood-sucking insect, Panstrongylus megistus (Burmeister) (Hemiptera, Reduviidae) Leia mais sobre Effect of sequential heat and cold shocks on nuclear phenotypes of the blood-sucking insect, Panstrongylus megistus (Burmeister) (Hemiptera, Reduviidae)