Porcupine

Porcupine, name for large, spiny vegetarian rodents of two distinct families: Erithizontidae, confined to the Americas, and Hystricidae, to the tropics of the Old World. Old World forms, including about a dozen species in Africa and South Asia, are among the largest rodents, and the entire body is covered with spines. The American porcupines have an equal armory of spines, but when relaxed, these are concealed in a thick underfur.