exuvia

/ɛɡˈzuːviə/
noun
  1. The shed outer skin or shell of an animal, such as an insect, spider, or crustacean, after molting.
    • The cicada's exuvia was still clinging to the tree trunk.
    • We found a crab exuvia on the beach, perfectly intact.
    • Under the microscope, the exuvia showed the fine details of the insect's legs.
Synonyms