We found this growing under a tree at our home here in Arizona when we moved here. It wasn't doing well at all. We transplanted it so it would get more sun and less water and since then, it has been rewarding us with spectacular blooms overnight. Can anyone identify it? I've searched the internet with no success. Also, is there anything special we should or shouldn't be doing to it to help maintain it? It looks like it might have been part of a small potted cactus assortment at one time and the previous owners not knowing what to do with it, simply planted it in any available dirt.

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