Here it is circled.
It's more than likely an illusion.
That is what I thought you were reffering to and here is the cropped piece that i was reffering to when i say there is also a second area that looks suspicious. It looks kind of like a face but is not detailed enough to draw a conclusion just as I don't think either of them have enough detail to make any conclusions. Oh and this crop is also lightened to bring out the "face". It is at the bottom center in the original photo (but a little to the right). In this crop the face is almost dead center but toward the bottom.