Imago

In biology, the imago (Latin for "image") is the last stage an insect attains during its metamorphosis, its process of growth and development; it is also called the imaginal stage ("imaginal" being "imago" in adjective form), the stage in which the insect attains maturity.

[1] In a member of the Ametabola or Hemimetabola, species in which metamorphosis is "incomplete", the final ecdysis follows the last immature or nymphal stage.

In members of the Holometabola, in which there is a pupal stage, the final ecdysis follows emergence from the pupa, after which the metamorphosis is complete, although there is a prolonged period of maturation in some species.

[1] Members of the order Ephemeroptera (mayflies) do not have a pupal stage, but they briefly pass through an intermediate winged stage called the subimago.

Insects at this stage have functional wings but are not yet sexually mature.