What is crustoce?

Crustoce is not a widely recognized term; it may be a misspelling or a niche term not commonly found in standard references. If you meant "crustacean," that refers to a diverse group of arthropods that includes crabs, lobsters, and shrimp, characterized by their hard exoskeletons. If you have a specific context in mind for "crustoce," please provide more details for accurate information.