Solved – this is Passiflora lutea!
Perhaps some of my taxonomically astute readers can ID this species:
Is this Passiflora lutea? I found it in an empty lot while on a walk and took some photos. I had no idea what it was, but some Google searching makes me think it may indeed be the “yellow passionflower.”
I think I may need to save one for my yard.
UPDATE: This plant is indeed Passiflora lutea – thank you all for the plant ID help!
NOTE: Passionflower vines are host plants for butterflies and also fill in a niche as a native plant. Though we may not know all they’re good for, they’re in the ecosystem for a reason. The woods around here have Passiflora incarnata but this is the first I’ve seen of this species.