Gymnocalycium nigriareolatum
Gymnocalycium nigriareolatum is a species of Gymnocalycium from Argentina.
Description
Gymnocalycium nigriareolatum is a cactus that grows either as a solitary plant or in clusters. It has dull, light to dark gray-green, rounded stems that are 4–6 cm tall and 5–8 cm wide. The plant typically has 10 sharp-edged ribs with shallow, transverse notches. It lacks central spines but has about 7 slightly curved, light gray-brown radial spines with darker tips. These spines are 1–3 cm long, with the 3 lowest being the longest.The flowers are funnel-shaped, either white with a pinkish throat or carmine red. They measure 4–4.6 cm in length and up to 4 cm in diameter. The spherical fruits are small, about 1–1.2 cm in diameter.