This cactus, which grows in the south of Brazil and Paraguay, in Uruguay and in north-west Argentina, was described as early as 1827 in honor of the German botanist Christoph Friedrich Otto. It used to be called Notocactus ottonis and is certainly still in many collections under this name. In 1987, however, all Notocacti were regrouped to Parodia.
The yellow flowers reach a diameter of up to 6 cm. The purpur style makes an interesting contrast.
Plants about 5 cm in diameter, about 3 cm high