1st one:
I have a Hylocereus in mind. Am I right?
It never bloomed as far as I remember.
help me out please :)
The one in the last picture on the right is definitely a Mammillaria bombycina the one on the left looks like a Echinocereus nivosus. The second cacti pictured looks more like a Trichocereus pachanoi to me. Although I guess that's now included in Echinopsis. I don't know anything about the Hylocereus.
Andy
Andy