Ecdysozoa

Ecdysozoa is a large group (supergroup) of animals characterized mainly by their ability to molt, or shed their outer covering, as they grow. This outer layer, called the cuticle, is often a tough, flexible shell that provides protection and support. As they grow, these animals shed the old cuticle and form a new, larger one. This group includes familiar creatures such as insects, arachnids (like spiders and scorpions), and many tiny worms called nematodes. Ecdysozoans are a key part of Earth's biodiversity and play crucial roles in ecosystems.