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the final (definitive) stage of individual development in insects. The characteristic features of the imago are full development of the wings and the presence of genital appendages at the end of the abdomen. In this stage insects migrate and reproduce.
In insects with complete metamorphosis (for example, butterflies, beetles, Hymenoptera, and Diptera), the imago develops from a pupa. In insects with incomplete metamorphosis (Or-thoptera, Dermaptera, Jugatae, and Hemiptera), a larva (nymph) hatches from the ovum, which resembles the imago in the structure of its mouth apparatus and its extremities but which metamorphoses into an imago only after a series of molts.
Insects live in the imago stage from a few days to several years. In some mayflies longevity is measured in hours; in the Psychidae family (of butterflies) in minutes; some beetles—weevils and nocturnal ground beetles—live in the imago stage two to three years; queen bees live up to five years; and female ants up to 15 years.