This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Mapinguari (Brazilian mythology)
The mapinguari is a monstrous cyclops giant. But unlike other cyclops, the mapinguari has a mouth protruding from its abdomen. Also called the juma, the mapinguari is described as a hulking, hairy creature with a body not unlike Bigfoot but just one eye, a gaping mouth, ape-like ears, and a second, protruding mouth in the center of its stomach region.
Others have described the mapinguari as somewhat resembling a giant ground sloth, a now extinct beast that lived in the Amazon region during the last Ice Age. Modern sightings describe a giant, hairy ground sloth similar to the South American Megatherium or the North American Megalonyx.