biology Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and ...

, the imago (

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

for "image") is the last stage an

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

attains during its

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and different ...

, 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. It follows the final

ecdysis Ecdysis is the moulting of the cuticle in many invertebrates of the clade Ecdysozoa. Since the cuticle of these animals typically forms a largely inelastic exoskeleton, it is shed during growth and a new, larger covering is formed. The remnant ...

of the immature

instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...

s. 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 Holometabola (from Ancient Greek "complete" + "change"), also known as Endopterygota (from "inner" + "wing" + Neo-Latin "-having"), is a supra-order (biology), ordinal clade of insects within the infraclass Neoptera that go through distincti ...

, in which there is a pupal stage, the final ecdysis follows emergence from the

pupa A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages th ...

, after which the metamorphosis is complete, although there is a prolonged period of maturation in some species. The imago is the only stage during which the insect is

sexually mature Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized as ...

and, if it is a winged species, the only stage that has functional wings. The imago often is referred to as the ''adult'' stage. Members of the order Ephemeroptera (mayflies) do not have a pupal stage, but they briefly pass through an intermediate winged stage called the

subimago Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the order ...

. Insects at this stage have functional wings but are not yet sexually mature. The Latin plural of ''imago'' is ''imagines'', and this is the term generally used by

entomologists Entomology (from Ancient Greek ἔντομον (''éntomon''), meaning "insect", and -logy from λόγος (''lógos''), meaning "study") is the branch of zoology that focuses on insects. Those who study entomology are known as entomologists. In ...

when a plural form is required –however, ''imagoes'' is also acceptable.Gordh, Gordon; Headrick, David H. (2010). "Imago". ''A Dictionary of Entomology'', 2nd ed. Wallingford, Oxfordshire, UK: CABI
p. 725
. .

References

External links

{{Wiktionary * Arenas-Mena, C. (27 February 2010)
"Indirect Development, Transdifferentiation and the Macroregulatory Evolution of Metazoans"
''Philosophical Transactions of the Royal Society B: Biological Sciences''. 365: 1540. pp. 653–669. Insect developmental biology

See also

References

External links