Acanthocereus tetragonus
is a species of cactus native to Mexico, Colombia, and Venezuela. It grows in rocky, arid, and desert habitats at elevations of up to 2,000 feet. Its stems grow up to two meters tall, and are covered with spines. It can be identified by its upright, cylindrical stems and its white, fragrant flowers. Its tall, spiny growth helps protect it from grazing animals and the elements.