The Loch Ness monster's existence has been declared "plausible" by scientists following the discovery of a fossil.
Researchers at the University of Portsmouth have made the claim after fossils of small plesiosaurs were found during a river system dig in modern-day Morocco.
Grainy images and descriptions of Nessie after alleged sightings have resembled the prehistoric plesiosaur - a marine reptile with four flippers which had a long neck and small head.
Sceptics had always dismissed the idea that plesiosaur lineage could have survived into the modern era and existed in Loch Ness though because the reptile could only inhabit a saltwater environment.
But the discovery of the fossils in a 100-million-year-old river system that is now in Morocco’s Sahara Desert suggests they lived in freshwater - like in Loch Ness.
The excavation unearthed bones and teeth from a 9.8ft long adult plesiosaur and an arm bone from a 4.9ft baby.
They indicate that the reptile cohabited with frogs, crocodiles, turtles, fish and the water-based dinosaur Spinosaurus in freshwater.
Dave Martill, a professor of palaeobiology at the University of Portsmouth who co-authored the research, said: “What amazes me is that the ancient Moroccan river contained so many carnivores all living alongside each other. This was no place to go for a swim.”
The teeth displayed the same patterns of heavy wear seen in the Spinosaurus. This supports the theory that the plesiosaur regularly preyed on the same heavily-armoured fish that lived in the river system as the Spinosaurus and was not just passing through the waters.
Dr Nick Longrich, corresponding author on the paper, said: “We don’t really know why the plesiosaurs are in freshwater.
“It’s a bit controversial, but who’s to say that because we paleontologists have always called them ‘marine reptiles’, they had to live in the sea? Lots of marine lineages invaded freshwater.”
The University of Portsmouth described the existence of the Loch Ness monster as "on one level, plausible" because plesiosaurs "weren’t confined to the seas" and "did inhabit freshwater".
The new research was published as a pre-print.
