Perhaps Mammillaria gracilis v. fragilis (Thimble Cactus), whose spines haven't thickened up yet. (Maybe needs more sun?)

lol, no it is not.

The funny thing is I actually DO HAVE a P. afra (pic in another thread), but I didn't know it. Very strange container for this one. I wonder if there's a pot inside the pot. I haven't molested this much until I figure out in what & with what this is going to live.

It's likely best in its own pot - certainly that nice plant will make a more powerful statement on its own, no?

Yes, I agree that this one is going to live by itself.
I'm trying to get an idea of expected root depth, so I can figure out what size pot to put it in. I'm thinking unglazed clay, but maybe not terra cotta-coloured, if I can find something else.

Ariel,
These tend to spread out more than down (root wise and plant wise, they're prolific breeders so to speak, they're always making new cacti and they like to spread out across a pot), so a bonsai style pot would be perfect. Mine unfortunately isn't as large as yours, so it's making it's home in a 3 inch clay pot right now and getting squished in the process (it's already trying to spread out, but there's not much room haha)

Planto

Mine is much more white with needle coverage and spreads across a 7" pot. I guess there is a fair amount of variability in this species. Even in bloom color, it appears. There appears to be some overlap (?) with M. vetula sp. gracilis. it is greener with pink blossoms. I am confused, nothing new. Mine blooms almost white with a fleshy yellow tinge. On the white needles the blossoms are barely visible.

I do think a rather broad, flat bonsai pot would be a nice home for this! Thanks.

ariel7576,
Hi again. :) You're welcome. One note about these, the babies pop off very easily (I think I've managed to pop off about seven already), but they do root easily. From your photo, I can see a couple laying on top of the rest of the cacti; you can put those in the soil and start new ones.

On another note, I agree with Rose (rosemariero) in that it looks like it would enjoy a bit more sun. Usually the spines are closer together and you don't see as much green skin. These are full sun cacti, so no worries there about where to stick 'em. Perhaps with more sun, the needles will "thicken."

Planto

Unfortunately, because of the horrible saw tooth oak (it grows THROUGH the deck--they built the deck around this evil tree!), my lovely southern exposure doesn't get FULL sun. (I hate the tree for many reasons, including the catkins, the acorns, the SQUIRREL invader... but the city will make us plant 3 trees in its place if it is removed, and we may be close enough to the shoreline for the state to fine us as well.) I'm considering the front steps. It is very bright there, but that's the north side of the house. Anyway, the deck gets morning & then afternoon/evening sun. The full southern sun is blocked by the evil tree. (It is bright out there, but not full sun.) Yes, I should have considered all of this before allowing the plants to mysteriously appear, but....

ariel7576,
Well, what can you do? Sometimes they just jump in your cart!

Planto

I need to hook up a shock collar to the entrances to all nurseries & garden centres! I promised myself that I wouldn't get anything else until I at least had what I have now potted in something other than the plastic pots they came in. Nonetheless, I came home today with more!

Ariel,
I expect to see pictures soon! :)

Planto