Notocactus OTTONIS - Otto's notocactus, Notocactus ottonis, Parodia.
Notocactus is a genus of plants in the cactus family (Cactaceae), which modern taxonomy has entirely included in the genus Parodia. The name Notocactus remains in wide use, however, and seeds are almost always sold under it.
In nature, these cacti grow on highlands and in the foothills of Paraguay, Southern Brazil, Argentina, and Uruguay. Their stem is solitary, short-cylindrical or globose, up to 1 m (3.3 ft) high in adult specimens, dark green, with well-defined ribs. Most species do not form branches or offsets. On the crests of the ribs sit numerous small tubercles with pubescent areoles, from which emerge clusters of spines: from 1 to 5 brownish-red central and up to 40 short yellow radial ones.
Notocacti bloom early and very abundantly, with flowers large relative to the size of the plant. They form in the upper part of the stem or right at the apex. The flower is polypetalous, bell-shaped or funnel-shaped, and the thick short fleshy floral tube is densely covered with spines and bristles. The coloration can be yellow, orange, or red, petal bases are usually contrasting or more saturated, and stigmas are more often reddish. An open flower lasts about a week.
Otto's notocactus is distinguished by a flat-globose stem 5-11 cm (2-4.3 in) across, rich bright green in color. There are 8 to 12 ribs, rounded and weakly tuberculate, wide and obtuse, with areoles sitting at a distance of about 1 cm (0.4 in) from each other.
There are 10-18 radial spines, needle-like, yellow, and 3-4 central spines, sturdier, reddish-brown, up to 25 mm (1.0 in) long and slightly curved. The flowers are very large, 4-8 cm (1.6-3.1 in) across, bright golden-yellow, opening at the very apex in spring. The plant readily produces lateral shoots, and over time a single cactus turns into an entire small family.