Range Description

The range of this species encompasses approximately 2,870 square kilometres in the San Jacinto Valley and adjacent areas of western Riverside County, southwestern San Bernardino County (at least formerly), and northwestern and north-central San Diego County, California in the United States (Bleich 1977, Williams et al., 1993). It is found at elevations of 55 to 1,250 m asl (USFWS, 1997). As of the late 1980s, most extant populations were in western Riverside County, but the largest known population was on the Warner Ranch near Lake Henshaw, San Diego County (see Burke et al. 1991).