I hope you can help me i.d. a really interesting tree we saw while vacationing on South Padre Island ( southern tip of Texas, right on the border with Mexico) last week. I have been searching on-line, but with no luck!

It was a sprawling tree with fan-shaped, leather-y leaves. The most striking thing about the trees were the clusters of what looked like green grapes hanging from the branches. I could not get a good identification from anyone at the hotel. They referred to it as the "grapevine tree".

I took home some of the "green grapes", assuming they were the seeds. I'd love to learn more about this tree, and would appreciate anyone's idea as to what it might be.

Thanks!