Crustaceans
THE shellfish they are invertebrate aquatic animals, that is, they do NOT have an internal skeleton, BUT protect themselves through a TYPICAL armor called exoskeleton or carapace which circumscribes them in the group of Arthropods.
The crustaceans used in human nutrition they are the Decapods, which further differ in: macrides, brachiuri and stomatopods; below we will analyze in more detail those most consumed in the diet of Italians (and not only).
NB. The origin of crustaceans is not always synonymous with greater consumption among the local population as, thanks (or rather ... CAUSE) of fishing and export, the use of products foreigners it is now part of the daily diet.