Sulcorebutia langeri

I may not have this identified correctly - but for now it is the best I could find. The flowers on this little cactus are absolutely brilliant. If I tagged it correctly, it actually will need to be water from March until September.

It will take full sun exposure, but needs light shade in Phoenix, Arizona.

I will continue to search for one of these in the local nurserys to see if I can find/validate the name on this plant.