who clears up this mystery

Here is a little mystery for you. Who will solve this riddle. It's not that easy it looks like..



Good luck!

It would, of course, be far too easy to say it is a spineless cultivar of M. luethyi. So I won't!

The heads look quite small, but as it is some montrose form, I don't think one can base anything on this. The odd thing is that I can't see the axils, the tubercles are so tight together.

So, no answer at the moment.......

It looks like it might be one of those hybrid M.gracilis that originated in Spain a few years ago, althought those plants did have a few short central spines.

Very good answers Chris and Tam.

Tam, I guess you speak about Mammillaria gracilis cv Arizona Snow Cap. I did expect this answer. And you're right this cultivar have short spines. But without reading-glasses I can't see the difference.

Chris, yes it's a montrose form and you're right that it's impossible to identify the mother plant.

The origin of this mutation is Mammillaria albicoma. It's amazing how similar those cultivars looks.
Here is a picture of the Snow Cap and one of the whole M.albicoma.

Thank you for your contributions.