Ball cactus

The term ball cactus is usually applied to the species of:
 * Parodia (syn. Notocactus), a South American cactus genus often kept as houseplants

It has also been applied to any ball-shaped cactus, notably plants from all of the following genera:

And more specifically to:


 * Escobaria missouriensis, the Missouri foxtail cactus or common ball cactus
 * Escobaria vivipara, the spinystar or purple ball cactus
 * Gymnocalycium mihanovichii, the ruby ball or "moon" cactus
 * Parodia leninghausii, the golden ball cactus or lemon ball cactus
 * Parodia magnifica, the ball cactus or balloon cactus
 * Parodia scopa, the silver ball cactus
 * Pediocactus simpsonii, the mountain ball cactus