| The Small-toothed Harvest Mouse apparently lives only in mature mountain forests where there are fallen trees, mosses, and ferns, so it could easily be threatened by habitat loss. It is semi-arboreal. It has long, thick whiskers and fur; the fur on its back is brownish or reddish, mixed with long, black hairs, and its sides are bright orange. It resembles the Mexican Harvest Mouse, but is smaller and is usually found at lower elevations.
Reithrodontomys microdon’s name is all about its teeth. "Reithrodontomys" means "groove-toothed mouse" and the "micro" in microdon suggests its teeth are tiny. In fact, Harvest Mice are all tiny mice with tiny teeth. They are very similar in appearance to Deermice (Peromyscus), which are also tiny creatures, but unlike Deermice, Harvest Mice have a small groove on their upper incisors.
Harvest Mice are strictly nocturnal, and typically snuggle together in self-built nests during the day and on bright moonlit nights. Even in a laboratory setting, where there were no predators, Harvest Mice only ventured out when the lights were off. When they forage, mostly for insects and seeds, they usually use pathways through the grass made by other small rodents.
Head and Body: 50-145 mm; Tail: 45-115 mm
Merriam, C.H., 1901. Proceedings of the Washingon Academy of Sciences, 3:548.
Mammal Species of the World