A study of the riparian vegetation of the riverbed and coastal ecosystems of the lower basin of the Mayo River. This is the most recent research carried out on the situation of the flora in this region located in northwestern Mexico; its floristic composition, an analysis of the plant community and a brief diagnosis of its affectation due to the exploitation of natural resources, once abundant and now scarce, paying the costs of a development based on agricultural activities and an incipient industrialization of primary products, in the coastal plain of the Mayo Valley in the southern region of the state of Sonora, Mexico.