As I've posted before, I'm hopeless at identifying cacti. My poorly-educated guess is that I've got something Rebutia-ish here. I was hoping to get a picture of the flowers in their prime, but I just missed on some and am too early for the others. I decided to take the picture now, lest I forget and not get any pics of the flowers at all.

{{gwi:471357}}

I'd greatly appreciate any suggestions.