When dinosaurs were the apex land predators, a trio of huge crocodile-like animals muscled their way through European waters.
One of the three, Machimosaurus hugii, measured well over 30 feet long and is thought to have feasted on dinosaurs unlucky enough to have crossed the path of this beast, according to geoscientist Mark Young.
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"There is a dinosaur femur with bite marks on it that resemble bite marks found on sea turtle shells," Young, of both the University of Edinburgh and the University of Southampton, told Discovery News. "It isn't clear whether Machimosaurus attacked dinosaurs, or would scavenge dead dinosaurs."
Young and his colleagues analyzed the remains of Machimosaurus, which was a genus of teleosaurid, as well as its relatives. These animals were marine "crocodyliforms," similar in appearance to today's crocs.
A paper about them is published in the journal Royal Society Open Science.
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Reviewing the fossils, the researchers determined that three different species of Machimosaurus lived during the Jurassic in what is now Europe:
Machimosaurus buffetauti- This is a newly described species. It measured around 20 feet long and lived in what are now France and Germany.
Machimosaurus mosae- According to Young, this croc was "adapted for living in turbulent coastal waters." Specimens are only known from northern France. It was larger than M. buffetauti, and measured 26 feet long.
Machimosaurus hugii: This was the likely dino eater and the biggest of the bunch. "It was adapted for swimming in open seas," Young said. "Specimens have been found in Portugal, Spain and Switzerland. It was the largest croc of the Jurassic and had the most bulbous teeth of any Machimosaurus species."
The researchers described yet another similar species from the time, Machimosaurus nowackianus, but it wasn't part of the European trio. This species lived in what would have been coastal Ethiopia. It proves that the crocs, as a collective genus, were a global force to reckon with during their lifetimes.
While the animals looked similar to today's crocs, they are not closely related to them. The study therefore offers a snapshot of long-dead animals that were like the evolutionary pioneers of the alligator/croc family.
Young explained, "Teleosaurids, along with the dolphin-like metriorhynchids, were the first aquatic/marine radiation of crocs. This teleosaurid+metriorhynchid lineage went extinct in the Early Cretaceous."
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The image of the three crocs here therefore reconstructs predators that haven't been alive since around 125 million years ago. As the image shows, a human diver would have just been a tiny snack for these large, toothy meat eaters, so perhaps we should be glad that they are no longer with us.
The prehistoric croc's actual favorite food? Young says it was turtles.
Image: Recreation of Machimosaurus species from Europe with a modern human for scale. Credit: Mark Young