United States, Mexico. Camponotus fragilis occurs over most of the Lower California peninsula as far north on the Gulf of California coast at least to Bahía de los Angeles and northwest into southern California via San Diego County. It is also present on most, if not all, the islands of the Gulf of California and in the State of Sonora and north into Arizona (Tempe, Maricopa Co., the easternmost record) in the United States; from Sonora it ranges south along the coast to Nayarit: specimens that I collected on the Tres Marías Islands apparently are referable to C. fragilis. In California C. fragilis appears to be uncommon and is replaced in the lower desert of Imperial and Riverside Counties by Camponotus absquatulator. It is present in chaparral habitat in San Diego County, north to Riverside County and is found at mid-elevation sites along the margins of the lower desert, extending north into the Mojave Desert at least as far as the Old Woman Mountains (1.2 km S Sunflower Springs, 945 m), San Bernardino County. (Snelling 2006).