The species is native to the southwestern and central United States and northern Mexico.

[2] The subspecific name, bunkeri, is in honor of American zoologist Charles Dean Bunker (1870–1948).

[3] The subspecific name, campi, is in honor of American paleontologist Charles Lewis Camp.

[2] The subspecific name, dickersonae, is in honor of American herpetologist Mary Cynthia Dickerson.

[4] H. maculata is found in the U.S. states of Arizona, Colorado, Kansas, Oklahoma, Nebraska, New Mexico, South Dakota, Texas, Utah, and Wyoming, as well as in the Mexican states of Chihuahua, Coahuila, Durango, Guanajuato, Jalisco, Nuevo León, San Luis Potosí, Sinaloa, Sonora, and Zacatecas.