Which apterygote groups are considered possible ancestors of winged insects?

The term apterygote is broadly used to describe primitive wingless insects, but its application in evolutionary biology is often restricted to groups considered the potential ancestors of winged insects (Pterygota).1

The groups identified as possible ancestors of winged insects include:

• Zygentoma: This order includes silverfish, fishmoths, and firebrats.1
• Archaeognatha: Commonly known as bristletails.1
• Monura: An extinct order of primitive hexapods.12

While other groups—such as proturans, collembolans, and diplurans—are traditionally grouped with apterygotes due to their wingless state and six-legged body plan, many modern entomologists classify them as independent classes that represent offshoots from the main insectan evolutionary stem rather than direct ancestors of winged insects. The groups considered potential ancestors are distinguished by their ectognathous (exposed) mouthparts, whereas the other groups possess entognathous (retracted) mouthparts.123