There's an entry in garden.org's database under Dragon Fruit (Hylocereus undatus), which seems to fit your identification of this plant. Why not ask to have your photo moved there? I see that you already have at least one photo of this plant in that gallery already. Not sure how this one ended up here, but it's fixable. Pity to have such a great photo 'orphaned' like this. Good luck. - Elizabeth
