Caligo illioneus has a wingspan reaching about . In this large
owl butterfly the dorsal sides of the wings vary from light brilliant blue to purplish with dark brown edges, while the undersides have a highly
cryptic dull brown color, with huge yellow-rimmed
eyespots resembling to the eyes of an
owl. In the early stage the caterpillars are greenish with yellow stripes along the body, about long. Later they are light brown with dark brown longitudinal stripes, about long. The caterpillars grow on banana plants, causing the destruction of large areas of banana plantations, while the adults mainly feed on the juices of fermenting fruits. ==Distribution==