At first glance, it looks like 5 finger prints. You can even see the finger nails as arcs at the top. But then stop a minute.... When you push on something with your hand, the nail of the thumb is always inverted. Try it and see. So this looks like 4 fingers, but the thumb nail arc is upside down from where it should be. I've seen this before, but always with the 5th finger, the thumb, being inverted.