Enormous reptile similar to ‘Loch Ness monster’ found in Antarctica

Palaeontologists working in Antarctica have pieced together the fossilised remains of an enormous sea creature similar to the mythical Loch Ness monster.

Argentinian researchers have uncovered “very important” fossilised remains of a specimen from the icy depths of Antarctica unlike anything seen before. A member of the reptile family elasmosaurid, the creature is now the largest of its kind discovered so far.

Palaeontologist José O’Gorman of the Museum of La Plata and a scientific agency at the Universidad Nacional de La Matanza, as well as fellow researchers, have noted the creature’s similarity in shape to the mythical Loch Ness monster, with its long neck and a body length of between 11.2 and 12 metres.

Publishing the discovery to Cretaceous Research, the researchers said the reptile would have been around close to the end of the Cretaceous period, prior to the sudden mass extinction event that led to the end of the dinosaurs.

The remains, now displayed at the museum, include part of the creature’s spine, anterior and some elements of its scapular waist. While its skull has not been found, the researchers have analysed what feeding strategy it might have had to develop to such a large size.

“It weighed between 10 and 13 tonnes, so it is well above those that were known until now, which had a mass of between five and six tonnes,” O’Gorman said.

Within the grouping of elasmosaurids, this giant reptile was part of the subfamily of aristonectinos, which had a slightly shorter neck, much more robust vertebrae and a much larger skull.

Scale of the creature when compared with a human. Image: Universidad Nacional de La Matanza

A battery of teeth

Explaining further, O’Gorman added: “The hypothesis that could explain the great size of this new specimen … is that the aristonectinos had a way of capturing their prey different from the rest of the elasmosaurids.

“We believe that, instead of capturing their prey individually, these animals opened their mouth and captured a large number of small prey at the same time, such as small crustaceans.”

This capture method is similar to how current whales feed, where they take advantage of a roughness on their palate to catch plankton. By comparison, the aristonectinos used a battery of teeth as their own food catcher.

“It seems that evolution repeated certain patterns of development between these two groups that have no relationship,” O’Gorman theorised. “Plesiosaurs are reptiles and have nothing to do with cetaceans that are mammals.”

The first samples of the creature were discovered way back in 1989 on Marambio Island in Argentine Antarctica at the western tip of the continent. Over the years it has been pieced together, with its current structure completed in 2017.

Located within sediments of an ancient, shallow marine environment, the region has also revealed fossil deposits of flying seabirds and dinosaurs of different groups.