Found in a band that extends from the Great Plains south through New Mexico and northern Mexico, Grusonia clavata is a hansomely spined, segmented, clumping cactus. It forms low growing mats and mainly propagates from detached segments. Segments are fairly small 2 to 4 inches long and an inch thick. Flowers are yellow and appear in late spring.
This came from Bachs Cactus Farm. I detached a few segments and the rest will go in the ground next year. Below is a closeup of the spination.