29-07-2025
152 Million Years Ago This Fish Met A Gruesome End
Around 152 million years ago, a fish met a gruesome end. The 15-centimeter-long animal died an ... More agonizing death, impaled on a 10-centimeter-long belemnite.
Around 152 million years ago, a fish met a gruesome end worthy of a punishment inflicted by Vlad III, commonly known as Vlad the Impaler, on his enemies. The 15-centimeter-long fish died an agonizing death, impaled on a 10-centimeter-long belemnite.
Tharsis is an extinct genus of marine ray-finned fish known from the Late Jurassic Solnhofen formation of Germany. These fish are known for their tiny teeth and are classified as micro-carnivores, feeding on zooplankton, or scavengers. In a new study, Martin Ebert and Dr. Martina Kölbl-Ebert from the Ludwig-Maximilians-University München report the discovery of four specimens of Tharsis that met their gruesome end while feeding on the decaying remains of belemnites.
Belemnite rostrums are long, cone-shaped calcium-carbonate shells found in an extinct group of mollusks, but unlike ammonoid shells, they supported the living animal's body from within and were completely covered in soft tissue. Belemnite rostrums come in various sizes and shapes, yet they all share a cone-shaped form ending in a pointed end.
Belemnites are rare in the limestone of Eichstätt and Solnhofen, where the described specimens were found. A rough survey of the most important collections revealed around 120 belemnites compared to some 15,000 fish. Likely they preferred the open sea, while the Solnhofen formation was deposited in a shallow lagoon. Likely only dead individuals, floating as gases formed by putrefaction accumulated in body cavities, entered the lagoon. The heavy rostrum dangling from the decaying remains like a lure.
Tharsis was likely feeding on such a floating belemnite, when the fish partially swallowed the rostrum beginning at the pointed end. Trying to dislodge it, the rostrum punched through the gills, impaling the animal and slowly choking it to death.
Modern-day observations support this interpretation, as fish (and unfortunately many other sea creatures) are killed while swallowing human-made products. Trash in water is soon overgrown by algae and bacteria. In combination with the shape of the floating object, this seemingly fools many animals to swallow it whole. The trash kills by obstructing gills, choking animals to death, or blocking the digestive system, as the plastic can not be digested.
The full study, "Jurassic fish choking on floating belemnites," was published in the journal scientific reports and can be found online here.
