I have 3 of these in a cool greenhouse with orchids. Fleshy with strange, primitive growth pattern. New leaves from ribs of old and sudden tall shoots from older stems bearing a single slender leaf. Never flowers for me.
I have one of these, aka night blooming cereus... it did bloom quite a magnificent but very shortlived flower that seemed to take forever to develop. True to its name, we realized we'd missed it cuz it was suddenly all over and the big pinkish white flower was wilted. This plant shoots out and takes off in all directions. Ours sent out a tip that didn't spread into foliage, but like a skinny green finger looking for sustenance it went up to touch the ceiling and started down again ... at that point we cut it off. Chunks of it will root easily for lots more plants. You can see pictures of it in Wikipedia.