The Ryukyu mouse is a rare rodent species found in the Ryukyu Islands of Japan. Also known as the Okinawa wood mouse, it has distinctive fur coloration and is critically endangered due to habitat loss and predation by invasive species. Synonyms for the Ryukyu mouse include the Okinawa mouse, Ryukyu spiny mouse, and Ryukyu tree mouse. These names reflect the species' geographic and ecological characteristics, as it is adapted to living in trees and shrubs on the islands' rugged terrain. Conservation efforts are underway to protect and restore the habitat of the Ryukyu mouse, which plays an important role in the island's biodiversity.