Microtus

Microtus 

(meadow mice), a genus of rodents of the subfamily Microtinae. The body length reaches 20 cm; the slightly or moderately bushy tail is no greater than one-half as long as the body. The molars have no roots and are ever-growing. The coloration of the upper parts is usually grayish brown; the lower parts are lighter, sometimes white.

Meadow mice are distributed in Eurasia and North America from the tundra to the subtropics; in the mountains they are present even in the alpine zone. There are approximately 60 species, assigned to four subgenera (according to other data, five to ten subgenera). In the USSR there are 12 species of the subgenus Microtus. The most common species are M. arvalis and M. oeconomus. Meadow mice feed mainly on green parts of plants and on roots; some store a substantial quantity of roots. In winter the mice usually congregate in haystacks and similar places. Many species are characterized by mass reproduction. Most meadow mice are dangerous pests of pasture plants and grain and fruit crops; they also are carriers of the causative agents of a number of diseases (tularemia, leptospiroses).