While in Charleston SC, near the battery, I saw several large shrubs or small trees blooming with yellow butter cup type flowers.

They were blooming in December. I do not know if this is its time to bloom or if the warm fall has made it bloom at a different time.

My photo shows a wilted flower. Fresh, its petals are cupped inward.

The leaves remind me of a sensitive plant as the leaves folded closed within a few hours of cutting.

I have never seen it where I live in zone 7b so I assume it only grows zone 8 and warmer. I also assume it must be growing in other southern states.

Does anyone know what it might be and how to propagate it?
Thanks in advance!