I believe it is the Echinocereus chloranthus Engelm
Common name: Brown-flowered Pitaya. Flowers range in color from yellowish brown to reddish brown, sometimes surrounding the plant between the middle and top. These plants are collected more for their beautiful spination than for their flower.
Does anyone know what this flower is? It was the last one left at my favorite nursery. They told me the name and I immediately forgot!
Commented on Jun 20, 2012
It grows much better and larger (like a shrub) in the soil but will tolerate a pot. It will
come back in the springtime if you cut it back (as it tends to kill the visible plant). The seed pods will open and distribute seeds everywhere near the plant. To prevent seedlings, you might want to cut the "green" pods off before they take over your flower garden. Save some of the dry seeds in a small container just in case your freeze is untolerable for the next year. They're easy to grow.