What's the difference between insects and arachnids?

L-R: Cicada (Insect), Scorpion (Arachnids)

There are many differences between insects and arachnids. Most are anatomical differences.
* The body of an insect is comprised of three segments: the head, thorax and abdomen. The body of an arachnid is comprised of two segments: the cephalothorax and abdomen.

* Insects have six legs; arachnids have eight legs.
* Insects have compound eyes; arachnids have simple eyes.
* Insects have antennae; arachnids do not.
* Many insects have wings; no arachnid has wings.
* Insects have mandibles; arachnids have chelicerae
* Insects undergo some form of metamorphosis; arachnids do not.
4 years ago