(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
Gymnocalycium horstii also called Spider cactus (because of its distinctively shaped spines is a gorgeous cactus with an interesting green ball shaped body.
Sun exposure: Light shade, (keep out of hot, direct sun)
Origin: Uruguay, East Paraguay, South Brazil and Northeast Argentina
Propagation: Seeds (seldom produces offsets)
Blooming habits: Pale pink flowers which bloom during mid spring, late Spring, early summer.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz