Blakrab, is there any foliage from the vine in the picture? It seems to be climbing a legume. The flower looks like it.

My 1st thought was Passiflora. This looks close to P. filipes. I believe those are passiflora leaves, sorry 😬

Wow, I wonder if this is actually a Yellow Passionflower (Passiflora lutea)?

Which brings us back to foliage. From what little foliage I can clearly see, nothing straight on , as your usual, I still think it's filipes. 😃 It really helps to see leaves straight on with visible vein patterns.

Does resemble a P. lutea flower that is not fully open yet... like this one:

Jay - Hmm, so what is the difference between Slender Passionflower (Passiflora filipes) & Yellow Passionflower (Passiflora lutea), as they look quite similar?

The foliage is different.🌿🌱☘🍃📸

Main difference is that P. filipes is much less likely to be found as far north as central Texas. Believe the most notable difference is that the center lobes on leaves of P. filipes are typically shorter and more rounded than those on P. lutea.

Edit - here's a link with short paragraph on the two: http://beta.semanticfna.org/Passiflora_filipes

OK, so here's some ~3"-4" leaves from the vine:

P. lutea