It's a Mirabilis species, perhaps nyctaginea, but would need a better picture of the leaves to confirm. These aren't the flowers, they are the bracts that held the flowers. That's the grenade shaped seed protruding from the bract. You have 13 Mirabilis species in Texas. I submitted Mirabilis nyctaginea a couple years ago, and I also thought the bracts were the flowers. It looks like maybe also a Clematis in that mix. Up here it would be virginiana, but again the leaves are too blurry to make out.