Echinopsis thelegona belongs to the family Cactaceae (the Cactus family). It is a bushy columnar cactus that is native to Argentina. This cactus is branching freely, semi erect or sprawling, and it can reach up to 1.2 m in height, up to 4 cm in diameter. The stems are dark green and have about 12 broad ribs. It has 1 central spines and 6 radial spines. The flowers are white nocturnal funnel-shaped, about 20 cm long, and bloom in summer. The fruits are red, hairy, and about 5 cm long. They split on one side, revealing black seeds when ripe.