Such a pretty species, native to Mexico. (Don't ask me how a Mexican species can be called "German Empress")
This is also commonly known as the "pond lily" cactus, due to the lotus-like blossoms. So delicate and lovely.
The bloom is about 3-4 wide, so this would be categorized as more on the small to medium size. Usually the branches will develop spotting. So far, on this particular plant, the spotting is very minimal. Just started from cuttings last summer, and has lots of new growth in less than a year!
Under evening light