from the Greek terms for joint and foot. More than 80% of the exisiting species on earth are arthropods. Arthropods are covered by a hard exoskeleton, providing physical protection. Arthropods grow in size by undergoing to periodic moults, exiting the old exoskeleton to form a new one.
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  - Kingdom ANIMALIA | |
  - Subkingdom EUMETAZOA | |
  - Phylum   ARTHROPODA |