5 or 6 years ago, a friend gave me 3 kinds of locally grown passionfruit. I planted seeds from all three; the red/purple ones have produced very well, and the yellow plants limped along for a while until I let them die from neglect (or maybe they're still there in the jungle, waiting their chance).

The leathery orange ones produced plants that have grown slowly but never produced fruit or flowers. And they aren't vines, they're rigid, erect, multi-stem bushes, about 8' tall now. Like maybe young trees. Oh, and they have inch-long thorns. I'm beginning to suspect this is some other kind of fruit (possibly a citrus)--or is there actually a spiny leathery orange passionfruit tree?

the photo is a composite of the tree, plus closeups of leaves and thorns.