The southern Idaho ground squirrel (Urocitellus endemicus) is a species of the largest genus of ground squirrels. This species and the Northern Idaho ground squirrel were previously considered conspecific, together called the Idaho ground squirrel.
The species has sexual dimorphism, with males being normally larger than females. Their weight ranges from 120g290g and are on average 233mm in length, though their range is 209mm258mm.
The southern Idaho ground squirrel can be found in an area about 30by extending from Emmett, Idaho, northwest to Weiser, Idaho, and the surrounding area of Squaw Butte, Midvale Hill, and Henley Basin in Gem, Payette, and Washington counties.
Its range is bounded on the south by the Payette River, on the west by the Snake River and on the northeast by lava flows. Their habitat is typified by rolling hills, basins, and flats at an altitude of between 670and.