Here's a brain-buster for you. It's believed that only one in a million of a species dies in such a way that permits the fossilization process to occur. Of those, only one in a million fossilize as an intact articulated specimen. Keeping those numbers in mind, how rare do you think this fossil is?
This is Mioplosus labracoides in an asphyxiation display, He choked on a Diplomystus dentatus that was too big to swallow or spit out. They're from the Eocene of the Green River Basin Formation in Wyoming.