The
coypu (, ;
Myocastor coypus), also known as the
river rat or
nutria, is a large,
herbivorous, semiaquatic
rodent and the only member of the family
Myocastoridae. Originally native to subtropical and temperate
South America, it has since been introduced to
North America,
Europe,
Asia, and
Africa, primarily by fur ranchers. Although it is still valued for its fur in some regions, its destructive feeding and burrowing behaviors make this
invasive species a
pest throughout most of its range.