Gymnocalycium achirasense v. orientale
(This plant comes in a 3.5 inch 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).
Flowers: They are some of the largest in this genus, often growing larger than the plant. 6 up to 7 cm long and broad, whitish, pale pink to lavender, with a darker mid-strip.
Cultivation and propagation: Summer grower, water regularly in summer, keep rather dry in winter. It grows well in full sun or light shade.
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz