The Parodia rutilans, whose origin is Uruguay, has beautiful pink flowers that are long lasting compared to other cacti I have in my collection. The flowers, which seem to bloom three, four, or five at a time in early spring, can last up to a week.
The P. rutilans, commonly called the Pink Ball Cactus, is one of 25 species formerly classified as members of the Notocactus genus. In the late 1980s, the Notocactus genus, along with seven other genera, was combined into the Parodia genus, much to the dismay of growers and collectors. One of the problems of combining several genera into one larger genus is that many of the cacti in a former genus have specific care requirements that are different from those of other formerly separate genera, who are all now called Parodia.
Former Notocactus species are grown for their spine formations as much as for the flowers. If you look closely at the spine formation on the P. rutilans in the photo, you can see the long central spines in very precise vertical rows.
The P. rutilans should be kept warm and on the dry side in winter, and watered regularly in summer. I keep it in light shade in the summer in Phoenix.