Pterygota

Bumblebee

• Mayflies ( Ephemeroptera)
• Dragonflies ( Odonata )
• Neuflügler ( Neoptera )

As flying insects ( pterygota ) all insects (Insecta ) are summarized, which are equipped with wings, including the groups of species that have lost the ability to fly again in the course of evolution ( examples fleas, louse, etc.). In this group corresponding to a part of the bulk of all insects, only the cliff divers ( Archaeognatha ) and fishes ( Zygentoma ) represent original types without flight ability is ( Apterygota or urine sects called ).

With the development of functioning wings hang a series of morphological and physiological changes together. For this reason, it can be assumed without doubt that this development has only taken place once in the course of insect evolution and all flying insects are due to a common ancestral species.

Construction and development of the wing

The wings are a thin Chitinplatte, which is traversed by tracheae. You have probably made ​​a flattening of the side plates ( Paranota ) on all three segments chest (thorax ) was developed. Today, however, live flying insects possess only two pairs of wings, each on the second and third thoracic segment. A third pair of wings could be detected in the fossil Stenodictya which had wing-like structures also on the first thoracic segment.

The tracheae supplying the wings branch off from the Beintracheen. Since the blades are designed as duplication (ie doubling ) of the body wall, the tracheae are as core network also in these two layers. With the thorax, the wings are connected by a complex joint, which was also directly attach the muscles at the dragonflies (direct flight muscles ). In the much more common variant of the wing beat is a bulge and a retraction of the chest segment achieved (indirect flight muscles ). Also necessary is the formation of muscle attachment sites in the chest segments by Chitinleisten.

Ontogeny of flying insects

All flying insects are characterized by a metamorphosis, as the larvae or nymphs never have wings. This can be done in steps with the molts (incomplete metamorphosis in insects hemimetabolic ) or by a complete reconstruction of the insect into a pupa ( complete metamorphosis in holometabolous insects)