This is currently my favorite cactus. It's adorable. Little fuzzy white areoles that cover sharp, nearly invisible spines. This was it's first flowering for me. It's one downside is it blooms at night and starts to close as the sun comes up, lasting only one night. I set my alarm for 4 am for this one and brought the flashlight.
Echinopsis subdenudata in bloom
E. subdenudata, better view of the plant
It's working on some more blooms now, as you can see from the grey fuzzy parts growing out from the areoles. I'll be up early to catch those too. It's tough to get good shots as the flower had already started to close by 5:30 am. Lighting isn't great that time of day, plus taking photos of something stark white in the dark is even more challenging.