Akodon spegazzinii, Spegazzini's grass mouse, is a rodent in the genus Akodon. It inhabits grassland and forest in northwestern Argentina at 400 to 3,500 m (1,300 to 11,500 ft) above sea level. Compared with other members of the Akodon boliviensis species group, it is medium in size, with a head-and-body length of 93 to 196 mm (3.7 to 7.7 in) and a mass of 13.0 to 38.0 g (0.46 to 1.34 oz). The coloration of its upperparts varies considerably, from light to dark and from yellowish to reddish brown. The underparts are yellow-brown to gray. The eyes are surrounded by a ring of yellow fur. The skull contains an hourglass-shaped interorbital region (between the eyes), and various features of the skull distinguish the species from its close allies. It reproduces year-round. First named in 1897, the species now includes mice that had been given other names from variable populations. Because it is common and widely distributed in its habitat
