Unusual cell in honeycomb

Hello all. We did an inspection on one of our hives and found this strange looking cell on one of the frames and we were wondering if anybody had seen something similar, or could say what it is.

When we checked the next frame, we found a queen cell. The queen cell is the only one we could find, although there were several queen cups on other frames.

It is probably a superscedure or an emergency cell. I would leave them alone.