Etymology -From the Greek diskos referring to the flat-round, disc shape of the plant stemsThe genus Discocactus is highly prized by collectors around the globe. Exactly what it is that makes them so attractive is uncertain. Some of the factors are likely their relatively compact size, unique and showy white flowers, and their slow growth. The species within this genus are flattened to globose in shape with stems that hardly exceed 3 inches (7.5cm) in height and are less than 10 inches (26 cm) in diameter. Stems are ribbed and sometimes tuberculate with fuzzy areoles or dense spines. Most plants remain single, but may form clumps. Flowering plants form a wooly terminal cephalium out of which rise the white flowers on the end of a long, thin floral tube. The nocturnal flowers are highly fragrant and touted by many growers as the best smelling of all cactus flowers.
Discocactus plants in the wild hail from Eastern South America and all are listed under CITES I due to habitat loss. In cultivation, plants are frequently grafted to speed seedling growth. A large number of names have been given especially for some species that are still used by hobbyists, but reduced to synonymy by many taxonomists.