For a moment I thought a flower had dropped off of something, and stuck between the leaves. But there are no plants blooming above it. So then, for a moment, I thought its own blossom had fallen and stuck there, but it's been a month and a half. By then, I was looking carefully. I took the first picture. If you look closely, you can see the purple part is kinda coming out of the middle of the leaf. Then I pulled the leaf off, and then it was clear that it was a partly-formed blossom.
A strange year for irises. First, I had these stunted jacarandas, and then I had the two-petaled dotted Swisses.