Old Man of Peru
Our blooms seem to only last a morning, not even a day. I took this photo in the early afternoon and the flower is already starting to close.
The buds are coming out of the lateral cephalium, the woolly area growing along the side of the plant.
You can really see the cephalium in this photo taken in habitat from Cacti Guide, photo by Craig Howe. And what a habitat that is, high altitude plains – looks kind of deserted, kind of desert like.