Pterygota

The Pterygota (Ancient Greek: πτερυγωτός, romanized: pterugōtós, lit.'winged') are a subclass of insects that includes all winged insects and the orders that are secondarily wingless (that is, insect groups whose ancestors once had wings but that have lost them as a result of subsequent evolution).[1]

Pterygota
Temporal range:
Giant honey bee Apis dorsata (order Hymenoptera) on Tribulus terrestris
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
(unranked): Dicondylia
Subclass: Pterygota
Lang, 1888
Orders
Odonata (dragonflies and damselflies)
Infraclass: Neoptera

For alternative classifications and fossil orders, see text.

The pterygotan group comprises 99.9% of all insects.[2] The orders not included are the Archaeognatha (jumping bristletails) and the Zygentoma (silverfishes and firebrats), two primitively wingless insect orders. Also not included is Entognatha, which consist of three orders no longer considered to be insects: Protura, Collembola, and Diplura.

Unlike Archaeognatha and Zygentoma, the pterygotes don't have styli or vesicles on their abdomen (also absent in some zygentomans), and with the exception of the majority of mayflies, are also missing the median terminal filament which is present in the ancestrally wingless insects.[3][4][5]

Systematics

Traditionally, this group was divided into the infraclasses Paleoptera and Neoptera.[6] The former are nowadays strongly suspected of being paraphyletic, and better treatments (such as dividing or dissolving the group) are presently being discussed. In addition, it is not clear how exactly the neopterans are related among each other. The Exopterygota might be a similar assemblage of rather ancient hemimetabolous insects among the Neoptera like the Palaeoptera are among insects as a whole. The holometabolous Endopterygota seem to be very close relatives, indeed, but nonetheless appear to contain several clades of related orders, the status of which is not agreed upon.

The following scheme uses finer divisions than the one above, which is not well-suited to correctly accommodating the fossil groups.

Infraclass Palaeoptera

(probably paraphyletic)

Infraclass Neoptera

Superorder Exopterygota

Superorder Endopterygota

Neoptera orders incertae sedis

  • Glosselytrodea †(extinct)
  • Miomoptera †(extinct)

References

Media related to Pterygota at Wikimedia Commons

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