This species occurs from the Central Mexican Plateau, to the west in northern Colima and north-central Sinaloa, including northwestern, central and eastern Michoacán, central and southern Jalisco, northwestern Guerrero and Oaxaca, and from central Mexico to the east into south-central Puebla, Tlaxcala and Veracruz, Mexico. It can be found between 610-2,400 m asl.
Habitat and Ecology
This species lives in a wide variety of habitats, from lowland xeric scrubs and deciduous forest to coniferous and oak forests. It is also recorded in disturbed environments. It breeds in streams.
This is one of the most common toads in Mexico, maintaining healthy populations along its range.
Desiccation, alteration and pollution of rivers and smaller streams are the main threats to this species, as it requires the presence of permanent, clean, shallow water.
The preservation of natural ecosystems including the river systems can guarantee the survival of this species. It occurs in a number of protected areas throughout its range.
This form is a complex of more than one species.
Georgina Santos-Barrera, Oscar Flores-Villela, Paulino Ponce-Campos 2010. Incilius occidentalis. In: IUCN 2014