The Japanese dormouse (Glirulus japonicus) is a species of rodent in the family Gliridae endemic to Japan. It is monotypic within the genus Glirulus. Its natural habitat is temperate forests. In Japanese, it is called yamane (ヤマネ or山鼠). Among dormice, it has the special ability of running at great speed upside down, suspended from branches. Its main food is insects, berries, nectar, or pollen.