Mammillaria hahniana??

I got this unlabelled one a while back, thought it was a form of hahniana, maybe bravoae?



It is almost indistinguishable from aff M saetigera WM5920 - it has slightly longer bristles, and larger tubercles than 5920. Here they are together, WM5920 is flowering


Then I found this plant when I looked at a possible mail order purchase - a pretty reliable vendor re names etc.



Hard for me to distinguish this -do you think it is named correctly?
When I look at Pilbeam, NCL and google, the two are related, and overlap geographically, but klissingiana seems to have shorter and whiter csp. Is there another key difference? I see also that Rogozinski and Plein refer the longer haired form of hahniani to klissingia, and the shorter bristled form to saetigera. Where do you guys come out on that debate

This is a common hahniana. Saetigera and also klissingiana are very related species.
The picture of klissingiana is not klissingiana. more geminispina leucocentra like.
I keep the hahniana name on my labels and the klissingiana name too, except for saetigera ssp.woodsii, a plant that I bought last year at Rogozinski. I haven't change that label. I'm still waiting for an explanation from Plein and Rogozinski why they prefer klissingiana and saetigera.

thanks, funny, I saw an albata from Woody that I almost put in the photo, and said it was different enough.
Are any of you aware of US sources of good mamms? The only vendors I know that I feel are extremely good are Woody and Mesa Gardens? My sense is European vendors are more careful, perhaps since more serious collectors there.
I still haven't got into growing from seed - so I am limited at this point in my selections.
Mike

I only know of Mesa Garden, Mike. When it was easier to import plants into the UK, I did buy some from Steven Brack. But now the import regulations are such that it really doesn't make sense, especiallywhen there are enough (although reducing) nurseries in the EEC where we dont have to worry about import permits, CITES etc.
But MG seed and therefore plants are pretty good, and ususally true.