You cannot keep an armadillo as a pet.

The Law

Maine has a very restrictive list of exotic animals that are permitted to be kept as household pets, and the leathery armadillo didn't make the cut. The prohibition exists primarily to prevent the introduction of foreign diseases, as armadillos are known carriers of leprosy. Given that they belong in warm, southern climates anyway, a Maine winter would not be pleasant for an armadillo.