A very rare fossil showed three different creatures in the middle of eating. This unique fossil from the early part of the Jurassic Period showed that a large marine creature (perhaps a shark) bit down on a squid-like creature that was already in the middle of feasting on a crustacean.
While the largest predator lived, the crustacean and the squid-like creature (called a belemnite) weren’t as lucky as their 180-million-year-old remains ended up at the bottom of a German sea. The remains were found in a small quarry that is located close to the town of Holzmaden in the southwestern part of Germany.
The fossil is incredibly rare as Christian Klug, who is the curator of the University of Zurich's Palaeontological Museum and a professor at its Palaeontological Institute as well as the lead researcher of the study, told Live Science that it is one of around “10 specimens of belemnites with [well-preserved] soft tissues worldwide.” This specific species of belemnite was called Passaloteuthis laevigata and it had 10 arms measuring about 3.5 inches in length with two rows of arm-hooks (400 of them in total).
Additionally, the fossil coined a new term called pabulite in reference to the “leftover” meal that was never digested by the predator and the remains ended up being fossilized. This referenced the belemnite that the larger creature (possibly a shark) chomped down on.
The researchers explained this type of “incomplete predation” by noting that the shark probably aimed for the belemnite’s soft and squishy areas on purpose as its pointy hard tip (called a rostrum) is very difficult to digest; therefore, the predator would have intentionally “bit off the soft parts, which were poorly protected.”
While it’s unclear as to what actually bit down on the belemnite, it very well could have been a Jurassic Period shark called Hybodus hauffianus as they were known to have eaten belemnites. Other big creatures may have preyed on it, like the large predatory fish Pachycormus and Saurorhynchus, an ichthyosaur called Stenopterygius, or a marine crocodile named Steneosaurus.
This fossil is a perfect example of how predators can quickly turn into prey for other creatures as Klug explained, “Predators tend to be happy when they are eating, forgetting to pay good attention to their surroundings and potential danger,” adding, “That might explain why the belemnite got caught, but there is no proof for that.” (Pictures of the fossil can be seen here.)
The study was published in the Swiss Journal of Palaeontology where it can be read in full.