The Oligoneoptera are the only cohort of superorder Endopterygota or Holometabola. They are insects of the subclass Pterygota, and are in the key taxonomic grouping whose general characteristic is nell'olometabolia. These insects have more larval stages of various aspect, however, quite different from the adult and without any trace of wings. In the larval stages following a quiescent nymphal stage (pupa), during which profound changes occur which will lead to an adult (picture) is completely different, morphologically and anatomically, from the larva. Sketches appear in the pupa of the wings. The ontogeny in this group grows so in the following stages:
egg - larva - pupa - The path to image larva in the image is under the influence of specific hormones: ecdysone and the neotenina (or juvenile hormone). The first leads the pack, the second inhibits metamorphosis. In the presence of
neotenina and ecdysone, the insects of this group through several larval stages in which they increased the size of the individual who makes, for the purpose, various sets. The wing buds are present during this stage as areas of undifferentiated cells called imaginal discs.
At one point, the concentration of neotenina failed and only in the presence of ecdysone, start the dormant stage called the pupa (chrysalis in butterflies), sometimes protected by a puppeteer or a cocoon. A pupa in which the appendages of the future adult are free is called exaracta pupa, and pupa obtecta is that if the appendices are welded to the body. During this stage many larval organs degrade or are absorbed at the same time, the originators of the new facilities mature their image. It happens that a complete structural revolution which will generate a new adult.
Taxonomy The Endopterigoti include at least 680,000 known species divided into ten orders, including those appearing evoluti.I most recent guidelines tend to overcome the division between classical and Endopterigoti Esopterigoti, including in the one group, based on the phylogenetic tree, called Neoptera. With this setting, it differed from the groupings of Endopterigoti Polyneoptera and Paraneoptera as the latest evolutionary branch, including the most advanced forms of Pterygota. The identification of ranks above the level of order, however, is controversial. The Endopterigoti can be identified in the rank of cohort, including only the superorder of Oligoneoptera, whose internal arrangement is based on the following plan:
Cohort superorder Endopterygota
: Oligoneoptera
Section: Coleopteroidea . Order: Coleoptera
(euolometaboli, ipermeboli, plometaboli)
Strepsiptera (hypermetabolism, catametaboli, criptometaboli)
Section: Neuropteroidea . Order: Neuroptera
(euolometaboli)
Section: Hymenopteroidea . Order: Hymenoptera
(euolometaboli, hypermetabolism, polimetaboli)
Section: Panorpoidea . Orders:
Aphaniptera (euolometaboli)
Diptera (euolometaboli, hypermetabolism, polimetaboli, criptometaboli)
Mecoptera (olometaboli)
Trichoptera (euolometaboli)
Lepidoptera (euolometaboli, hypermetabolism, catametaboli)
Another classification, fairly widespread, divides the order of the Neuroptera in three separate orders, the proper Neuroptera (or Planipennia) and the Megaloptera Raphidioptera.
Behavior
In this group, larvae and adults differ not only in appearance but also for the behavior: the larvae, since the purpose of accumulating material and energy, spend their lives, which can be relatively long to eat ; adults are intended principally to reproduce and their lives may also be relatively short.
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