Sorry: #1 and #10 are the same plant!!
davide

#8 appears to be a Notocactus Uebelmaniannus-?

Ah, you spotted #1 and #10! As it happens, I know this one. It is Parodia oxycostata (= Notocactus oxycostatus). It has huge yellow flowers all summer long, plus the nice purple skin in the sun.

Davide

Problem is that they are still a bit young.

I would suggest:

#4 Matucana madisoniorum
#9 Neoporteria (Eriosyce) spp
#11 Matucana paucicostata

Good luck with the rest

LOL

Fof

no. 4 Indeed Matucana madisoniorum
no 11. some Coryphanta,
Hablu

#11 maybe Coryphantha maiz-tablasensis?

Kate

Too many spines for maiz-tablensis, I don't think its a Coryphantha at all. Maybe a Matucana.

#5, #6, #7, and #8 may all be Sulcorebutia or close relatives.

I think #2 and #5 are also the same plant, aren't they?

Here's my best guess on your little bevy of new friends:

1: Notocactus ottonis cv. Aigua form
2: Gymnocalycium multiflorum
3: Notocactus roseoluteus
4: Matucana madisonorium
5: Gymnocalycium multiflorum
6: Lobivia draxlariana
7: Gymnocalycium bruchii
8: Notocactus, either arachnites or crassigibbus
9: Neochileana jussieu
10: Notocactus ottonis cv. Aigua form
11: Coryphantha andreae

Just guessing,
Mark

Thank you all for your help.....!!!!!!
(Right Mark, #2=#5!)
davide