What mammi is ¿?

Hello, i put this mammillaria to identify.

It has 7 radial spines and 1 central spine, I do not know what flower it has.

Thank you!

Hi,
Not really sure because it appears to be relatively small, but looking at the spines etc. I'll hazard a guess at m.petrophila. Someone else may come up with a more positive answer.

I was inquire and what is most similar is a mammi bocensis.