Appearance
While sometimes referred to as Golden Ball, this species is not to be confused with Notocactus leninghausii which have fuzzy, harmless spines and are native to Brazil and Paraguay.Growing as a large roughly spherical globe, it may eventually reach over a metre in height after many years. There may be up to 35 pronounced ribs in mature plants, though they are not evident in young plants, which may have a knobbly appearance. Note: Younger Golden Barrels do not look similar to the mature ones. The sharp spines are long, straight or slightly curved, and various shades of yellow or, occasionally, white. Small yellow flowers appear in summer around the crown of the plant, but only after twenty years or so.

Naming
Described by Heinrich Hildmann in 1891, it is popularly known as the Golden Barrel Cactus, Golden Ball or, amusingly, Mother-in-Law's Cushion.Status
Despite being one of the most popular cacti in cultivation, it is rare and critically endangered in the wild.References:
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