I got this about a month ago at a local nursery without a tag. Some have ID'd it as Discocactus buenekeri. I have read that the flower of this cactus is white but these appear to be yellow. I guess I should wait until they are opened before making that call but since they have a very short life, I might miss them later tonight.... so if someone has a better name for this, please don't be shy and speak up!!!!