In answer to your question of 'how'd you know that'...I didn't. No clue. But I was wondering if the vine would make a good houseplant.
I use key words like 'Texas Vine' in Google Images and look for the shape of the leaves. This is good excercise for my old eyes and helps me to better observe details.
When I find a photo similar to yours I click on the links, such as:
http://www.catnapin.com/WildFl... and
http://www.delange.org/GrapeIv...
I quickly read the details. If I have the wrong plant, I start over.
If I think I have the correct plant, I plug the botanical name from the link into Google Images and search again, looking for more details.
When I was a kid I thought that reading the encyclopedia was a fun pastime. The computer is my new encyclopedia; it helps that I don't have an active social life and have time to do this kind of thing.
Good luck with the plant.
