Apterygota Temporal range:
Petrobius maritimus (Archaeognatha: Machilidae)
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Subclass:	Apterygota†
Orders
Archaeognatha Thysanura Monura (extinct)

The Apterygota are a small subclass of primitive insects.

They are insects which have never had wings at any time in their evolutionary history. Their first known occurrence in the fossil record is in the Rhynie chert of the Devonian period, ~400 million years ago. While some other insects, such as fleas, also lack wings, these are descended from winged insects, and have lost them during the course of evolution. By contrast, the apterygotes are a primitive group of insects that diverged from other orders before wings evolved.

They have some other primitive traits (features).The nymphs (younger stages) go through little or no metamorphosis, so they look like the adults. They continue to moult throughout life, with multiple instars (stages) after reaching sexual maturity. All other insects have only a single sexually mature adult stage. Their skin is thin, making them appear translucent.