This species occurs in the northwestern United States, and formerly in southwestern Canada. It ranges from southern British Columbia (where it is apparently extirpated; Powell and Russell 1998) south to northeastern California, northern Nevada, and southern Idaho (Zamudio et al. 1997, Stebbins 2003); eastern and southern range limits have not been precisely determined; there is an old record from extreme southwestern Montana, where current status is unknown (St. John 2002, Werner et al. 2004). Its elevational range extends from around 300 to 1,830 m (1,000 to 6,000 feet) (Stebbins 2003).