Well, the next day I happened to be walking by the Orobanche again. Lewis had suggested that it would be fun to sit nearby and watch to see which pollinators visit these flowers. I was on my way to a meeting, but I decided to give it 5 minutes.
I waited 4 minutes, and no insects had come to the flowers. Why not? They seemed so perfect — wide open and ready for visitors. Should I leave? It had been 4 minutes already without any signs of activity. But I had told myself that I would watch for 5 minutes. So I gave it another minute.
With about 30 seconds to go, a small bee flew in! It dove into one flower very quickly, so I waited with camera poised until it appeared (see below). You can see it emerging head-first, crawling along the yellow nectar guides.
It then flew to at least 3 more Orobanche flowers. Because of its small size and unpredictable flight pattern the bee was difficult to photograph. These are the best images I have for now. I'll be sending the pictures out for help with an identification of the bee.
A view from above:
On the way to another flower (not such a bad place to bee!):
Emerging from the "tube":