The nine-banded long-nosed armadillo or just nine-banded armadillo, Dasypus novemcinctus (also known as the poor man's pig or poverty pig), is a species of armadillo from North, Central and South America. It is the most widespread member of the group. Its ancestors evolved in South America, but were able to invade North America during the Great American Interchange after the Isthmus of Panama formed 3 Ma ago.

The nine-banded long-nosed armadillo is a solitary, mainly nocturnal animal, found in many kinds of habitats, from mature and secondary rainforests to grassland and dry scrub. It is an insectivorous animal, feeding chiefly on ants, termites and other small invertebrates.

This species is the only known animal that is able to inflate its own intestine in order to float across a river. It can also hold its breath for up to 6 minutes in order to walk across the bottom of narrow rivers. Additionally, the nine-banded armadillo always produces four identical offspring. The armadillo can jump three to four feet (90-120 cm) straight in the air if sufficiently frightened, making it a particular danger on roads.

The nine-banded armadillo has been rapidly expanding its range both north and east within the United States. The armadillo crossed the Rio Grande from Mexico prior to the 20th century; by 1995 the species had become well-established in Texas, Oklahoma, Louisiana, Arkansas, Mississippi, Alabama, and Florida, and had been sighted as far afield as Kansas, Missouri, Tennessee, Georgia, and South Carolina. A decade later, the armadillo had become established in all of those areas and continued its migration, being sighted as far north as southern Nebraska, southern Illinois, and southern Indiana.

The primary cause of this rapid expansion is explained simply by the existence of few or no natural predators of the armadillo within the United States, little desire on the part of Americans to hunt or eat the armadillo, and the animal's high reproductive rate. It is speculated that the northern expansion of the armadillo will continue until the species reaches as far north as Ohio, Pennsylvania, and New Jersey and all points southward on the East Coast of the United States. Further northward and westward expansion will probably be limited by the armadillo's inability to tolerate especially harsh winters, due to having little body fat to protect it from the cold.

As of 2008, newspaper reports indicate that the nine-banded armadillo seems to have expanded its range northward as far as Lincoln, Nebraska in the west , and Nashville, Tennessee and the Land Between the Lakes region as far north as Kentucky Dam and Evansville, Indiana in the east.