1. Segmentation: Both crayfish and annelids have bodies composed of repeating segments. This segmentation allows for specialized functions in different parts of the body and provides flexibility and mobility.
2. Exoskeleton: While not as obvious in annelids, both have a tough outer layer that protects their soft tissues. Crayfish have a hard, calcified exoskeleton, while annelids have a thinner, more flexible cuticle that still provides structural support and protection.
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