Discocactus

Discocactus is a genus of tropical cacti. The name comes from the ancient Greek "" (=disc) because of its shape. "Discocactus" plants are endemic to southern Brazil, eastern Bolivia, and northern Paraguay. These species are in the risk of extinction in the wild.
The plants have a slightly flattened spherical shape. The areoles bear sharp spines. At the apex of the adult plants, there is a wooly cephalium, white or shaded with yellow or grey. The white nocturnal flowers appear on the sides of the cephalium. The fruits are pink or red and contain black seeds.