Ecdysozoa

animal group

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Last updated

July 19, 2026

Quick Summary

Ecdysozoa is a major group of animals characterized by ecdysis, the process of shedding their outer body layer, or exoskeleton, to grow or change shape. This shedding is also known as molting.12

Key facts about Ecdysozoa:
* Exoskeleton: They possess an external covering secreted by their epidermis, which is shed during ecdysis.2
* Growth and Development: Ecdysis is crucial for their growth and development, allowing them to increase in size and undergo metamorphosis.23
* Hormonal Control: The process of ecdysis is regulated by specific hormones and neuropeptides.2
* Examples: This group includes well-known arthropods such as insects, spiders, scorpions, mites, ticks, crabs, and shrimp.45

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nematode
…provisionally grouped together as the Ecdysozoa, a taxonomic category based on the assumption that molting has evolved only once. So far, gene sequence data from several molecules support such an assumption.
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…provisionally grouped together as the Ecdysozoa, a taxonomic category based on the assumption that molting has evolved only once. So far, gene sequence data from several molecules support such an assumption.
Read More