It looks like Mammillaria to me also but I have some questions.
I think there are tubercles under all those spines. If so, can you see the base of the tubercles? There should be a little spot or tuft or.. were the flowers are originating.
The flowers always grow on last years growth so generally in a ring around the top of each 'ball' in the cluster.
Are there hooks on the ends of any of those spines that you can feel when you slide you finger off the tip of a spine?
Is this growing wild?
Daisy
