Gymnocalycium is a genus of cacti known for its small to medium-sized, globular or cylindrical-shaped plants. They belong to the family Cactaceae and are characterized by their ribbed or tuberculated stems and often colorful flowers. Gymnocalycium cacti are native to South America, primarily found in Argentina, Uruguay, Paraguay, and southern Brazil. They are popular among cactus enthusiasts and collectors for their interesting and diverse appearances, as well as their relatively easy care requirements. These cacti can thrive in a variety of growing conditions, making them suitable for both indoor and outdoor cultivation.