''Erethizon'' is a genus of

New World porcupine The New World porcupines, family Erethizontidae, are large arboreal rodents, distinguished by their Spine (zoology), spiny coverings from which they take their name. They inhabit forests and wooded regions across North America, and into northern ...

and the only one of its family to be found north of southern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. The

North American porcupine The North American porcupine (''Erethizon dorsatum''), also known as the Canadian porcupine, is a large quill-covered rodent in the New World porcupine family. It is the second largest rodent in North America after the North American beaver (''Ca ...

''(Erethizon dorsatum)'' is the only extant species, but at least 4 extinct relatives are known, the oldest dating to the

Late Pliocene Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudo ...

. Porcupines entered North America during the

Great American Interchange The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land ...

after the

Isthmus of Panama The Isthmus of Panama, historically known as the Isthmus of Darien, is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North America, North and South America. The country of Panama is located on the i ...

rose 3 million years ago. Early species of the genus retained an elongate tail, unlike ''E. dorsatum''.

References

{{Taxonbar, from=Q732499 Rodent genera Mammal genera with one living species Taxa named by Frédéric Cuvier Erethizontidae