The Japanese dormouse (Glirulus japonicus) is a species of rodent in the family Gliridae. It is monotypic within the genus Glirulus. It is endemic to Japan. 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 or berry or nectar or pollen.