The Echinocereeae are a tribe of cacti in the subfamily Cactoideae. Since 2006, the tribe has included the former tribe Pachycereeae in many treatments of cactus classification. The exact circumscription of the tribe has been subject to considerable change, particularly since molecular phylogenetic approaches have been used in determining classifications, and remains uncertain. The tribe includes large treelike species, such as the saguaro (Carnegiea gigantea), as well as shorter shrubby species. Most members of the tribe are found in desert regions, particularly in Mexico and the southwestern United States.