What about these Mammillarias?

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Hello Sonja,
Your first is , no doubts the Mamm. formerly knowed as Lindsayi, but as I've mentioned here before in another topic, has nothing to do with lindsayi. The name is now: M. sinforosensis ssp. cobrensis.
The second one: The closest I can get is apozolensis, NOT the var. saltensis because the much longer spines, but the normal apozolensis
And the name for the 3th one: I've been looking in my greenhouse to a similar plant and I found exactly the same one. It has no fieldnumber but came from Deherdt Nursery who got it from Lau himself. Oh, you want a name: mine is labeled as M. sonorensis (yellow spined form)

Has Hugo rightly points out the first is the yellow flowering mamm from Areponapucui, Barranca del Cobra and more information can be found on the M.lindsayi Lau1135 thread under general questions. Just to make the point that in the new AfM journal 2008/2 page 101 Plein/Rogozinski are suggesting that this plant is nothing to do with M.sinforoensis but is a indepentent further development of M.craigii.

Thank you both,