This was sold to me by a reputable native plants dealer as a passiflora incarnata (Maypop). However, I've been seeing your photos and am now in doubt...what passiflora is this? Thanks!
SOLVED: Tim, which Passiflora?
There are a few leaves next to the other flower bud, are they from the vine in question? The leaves and the flower appeared to be from Passiflora caerulea.
Yes, those are its leaves. That's what I had decided it must be from studying your photos. Thank you. Now how do I tell that well-studied young man (plant dealer) he made a mistake?