What is the Difference Between Apterygota and Pterygota

The key difference between apterygota and pterygota is that apterygota is a subclass of insects comprised of wingless insects, while pterygota is a subclass of insects comprised of winged insects.

Insects are the largest group within the arthropod phylum. They are also the most diverse group of animals. Generally, an insect has a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes, and one pair of antennae. There are more than a million described insect species. They also represent more than half of all known living organisms. Furthermore, insects live nearly in all environments. Approximately over 90% 0f animal life forms on Earth are insects. Apterygota and pterygota are two subclasses of insects.

CONTENTS

1. Overview and Key Difference
2. What is Apterygota  
3. What is Pterygota
4. Similarities – Apterygota vs Pterygota
5. Apterygota vs Pterygota in Tabular Form
6. Summary – Apterygota vs Pterygota

What is Apterygota?

Apterygota is a subclass of insects that includes wingless insects. It is also a subclass of small agile insects. These insects are distinguished from other insects by their lack of wings at present and in their evolutionary history. This subclass normally includes silverfish, firebrat, and jumping bristletails. Their first occurrence in the fossils was recorded during the Devonian period. That is exactly 354 to 417 million years ago.

In their life cycle, the nymphs (younger stages) go through little or no metamorphosis. The younger stages hence resemble the adult specimens. The skin of the insects of this subclass is thin, making them appear translucent. Apterygota also has a number of other primitive features, such as males depositing sperm packages externally rather than fertilizing the female internally. These insects also have small appendages called “styli” which play no part in locomotion. In addition, they have long paired abdominal cerci and a single median tail-like caudal filament. Moreover, currently, no species of this subclass are listed in the conservation risk list.

Usually, the term Apterygota refers to two separate clades of insects that lack wings: Archeognatha and zygentoma. Archeognatha comprises jumping bristletails. On the other hand, zygentoma comprises silverfish and firebrat. Furthermore, in taxonomy, apterygota is a paraphyletic group.

What is Pterygota?

Pterygota is a subclass of insects that includes winged insects. It also includes insects that are secondarily wingless. Secondarily wingless refers to whose ancestors once had wings but have lost them as a result of subsequent evolution. The pterygota group comprises almost all insects except archeognatha and zygentoma, which belong to apterygota. This group does not include the three orders, proturan, clollembola, diplura, as they are no longer considered to be insects.

The history of insects of this subclass also goes back to the Devonian period. Pterygota subclass species always show metamorphosis. Furthermore, their adults do not mould and do not have pregenital appendages. The mandibles of these insects are articulated with a head capsule at two points. The most well-known insects of this subclass include mayfly, dragonfly, etc.

What are the Similarities Between Apterygota and Pterygota?

• Apterygota and pterygota are two subclasses of insects.
• They are classified under phylum Arthropoda.
• The first occurrence in the history of both subclasses goes back to the Devonian period.
• Both of them represent more than half of all known living organisms.

What is the Difference Between Apterygota and Pterygota?

Apterygota is a subclass of insects that includes wingless insects while pterygota is a subclass of insects that includes winged insects. So, this is the key difference between apterygota and pterygota. Furthermore, apterygota is a small subclass of insects, while pterygota is a large subclass of insects.

The below infographic lists the differences between apterygota and pterygota in tabular form for side by side comparison.

Summary – Apterygota vs Pterygota

Insects belong to the phylum Arthropoda. Insects live in nearly every habitat. Apterygota and pterygota are two subclasses of insects. Apterygota is a subclass of insects that includes wingless insects, while pterygota is a subclass of insects that includes winged insects. Thus, this is the key difference between apterygota and pterygota.

Reference:

1. “Pterygota.” Entomologists’ Glossary – Amateur Entomologists’ Society (AES).
2. “Apterygote.” Encyclopædia Britannica, Encyclopædia Britannica, Inc.

Image Courtesy:

1. “Archaeognatha” By User:Stemonitis – Self-photographed (CC BY-SA 2.5) via Commons Wikimedia
2. “Tramea basilaris, Family: Libellulidae Tramea basilaris..” (CC0) via Pxhere