This is Dyckia fosteriana nivosa a regional form of fosteriana. This is the one I found in a fig plantation close to Lapa in Paraná the Brazilian state just north from Santa Catarina and three and a half hours away from here.
As I did not asked for permission to show it here I won´t reveal the name of the sender.
I am so touched and moved.. I wanna say thanks, thanks and Aloha!
This is for you my friend in Hawaii: