Gymnocalycium gibbosum
Gymnocalycium gibbosum is a species of Gymnocalycium from Argentina.
Description
Gymnocalycium gibbosum usually grows singly with dark blue-green, spherical to short cylindrical shoots that reach a diameter of 10 to 12 centimeters. The twelve to 19 ribs are noticeably notched. The one to three central spines are often missing. The seven to 15 straight, stiff, light brown to almost black marginal spines are up to 3.5 centimeters long.The white or sometimes reddish flowers are up to 6 centimeters long. The dark green fruits are club-shaped.
Subspecies
There are two recognized subspecies.| Image | Name | Distribution |
| Gymnocalycium gibbosum subsp. borthii G.J.Charles | Argentina | |
| Gymnocalycium gibbosum subsp. gibbosum | Argentina |