New member and 4 new plants

Dear Mammillaria enthusiasts

I am new to this forum and have loved cacti since my childhood. However, towards Mammillarias I never felt any strong attraction until recently. When I detected a few very nicely thorned and shaped nameless species in one of these supermarket bowls I had pity with these nice guys. But, of course, I would like to find out their real names, origin, vegetation rules etc. Here we go, maybe you can help me (two pictures per plant, totally 4 plants):

















Thank you very much for your help!

Stephan from Switzerland

The first (two) pictures are that of M. microhelia and the last (two) pictures are that of M. columbiana.

Thanks a lot Amante.

Could the whilte spined (plant no. 2) be Mammillaria albilanata and the 3rd plant be a dark form of Mammillaria columbiana?

Thanks a lot.

Stephan

I am sure Amante is right on Nos 1 and 4.
No 2 should have central spines if it is albilanata. I can't see clearly enough. It certainly is from the Supertextae series.
And yes, your suggestion of a darker spined columbiana could very wel be right.

Thanks a lot, Chris. Well, no. 2 actually has one central spine, quite the length of the secondary spines, but slightly thicker with a brown tip. Then it is albilanata, right?