Imago

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Last molting of a cicada giving rise to the winged imago Cicada molting animated-2.gif
Last molting of a cicada giving rise to the winged 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, the stage in which the insect attains maturity. It follows the final ecdysis of the immature instars. [1]

Contents

In a member of the Ametabola or Hemimetabola, 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. [2]

The imago is the only stage during which the insect is sexually mature and, if it is a winged species, has functional wings. The imago often is referred to as the adult stage. [1]

Members of the order Ephemeroptera (mayflies) do not have a pupal stage, but they briefly pass through an extra winged stage called the subimago. Insects at this stage have functional wings but are not yet sexually mature. [1]

The Latin plural of imago is imagines, and this is the term generally used by entomologists  – however, imagoes is also acceptable. [3]

See also

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<span class="mw-page-title-main">Hemimetabolism</span>

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<span class="mw-page-title-main">Ontogenetic niche shift</span> Ecological phenomenon

Ontogenetic niche shift is an ecological phenomenon where an organism changes its diet or habitat during its ontogeny (development). During the ontogenetic niche shifting an ecological niche of an individual changes its breadth and position. The best known representatives of taxa that exhibit some kind of the ontogenetic niche shift are fish, insects and amphibians. A niche shift is thought to be determined genetically, while also being irreversible. Important aspect of the ONS is the fact, that individuals of different stages of a population utilize different kind of resources and habitats. The term was introduced in a 1984 paper by biologists Earl E. Werner and James F. Gilliam.

References

  1. 1 2 3 Carpenter, Geo. H., The Life-Story of Insects. Cambridge University Press 1913. May be downloaded from: https://www.gutenberg.org/ebooks/16410 or https://archive.org/details/thelifestoryofin16410gut
  2. Richards, O. W.; Davies, R. G. (1977). Imms' General Textbook of Entomology: Volume 1: Structure, Physiology and Development Volume 2: Classification and Biology. Berlin: Springer. ISBN   0-412-61390-5.
  3. Gordh, Gordon; Headrick, David H. A Dictionary of Entomology. Publisher: CABI 2010. ISBN   978-1845935429