Ancient marine crocodile species discovered after decades in Germany

An international team of scientists has described a new species of ancient marine crocodile, Enalioetes schroederi, which inhabited shallow seas about 135 million years ago in Germany. Dolphin-like bodies, smooth skin, flippers, and tail fins distinguished animals from Metriorhynchidae.

The perfectly preserved skull and neck vertebrae of Enalioetes schroederi were discovered over a hundred years ago by German architect D. Hapke in a quarry in Sachsenhagen near Hanover, as reported by Sci News. Unfortunately, the fossils of this ancient species went missing during World War II but were found years later in the Minden Museum in West Germany.

Initially, Henry Schroeder studied the new species from the Prussian Geological Survey in Berlin. The scientists who continued the analyses named the ancient crocodile in his honor. As explained in the "Journal of Systematic Palaeontology," Enalioetes schroederi belonged to the marine crocodyliform family Metriorhynchidae. This family is best known from the Jurassic period, with its fossils being much rarer from the Cretaceous period.

Members of Metriorhynchidae were fully adapted to life in the sea and developed numerous anatomical features to facilitate this lifestyle. These features include elongated, streamlined skulls with less weight, lighter ribs and femur bones due to greater porosity, short front limbs resembling paddles, and larger hind limbs similar to crocodiles.

Dr Mark Young from the University of Edinburgh's School of GeoSciences, who was involved in the research, noted: "Enalioetes gives us fresh insight into how metriorhynchids were evolving during the Cretaceous Period. During the Jurassic metriorhynchids evolved a body-plan radically different from other crocodiles – flippers, tailfin, loss of bony armour and smooth scaleless skin. These changes were adaptations to an increasingly marine lifestyle. Enalioetes shows us that this trend continued into the Cretaceous."

As Young explained, this is evidenced by the ancient crocodile's larger eyes and ear structure, allowing Enalioetes to swim faster than other Metriorhynchidae likely. Experts believe that Enalioetes schroederi fed on various prey, including fast-moving animals such as squids and fish, and it may also have preyed on other marine reptiles.