This giant fish lurked beneath the seas 375 million years ago

This drawing depicts Laccognathus embryi, a giant human-sized fish that prowled the ancient Arctic waters 150 million years before the emergence of the dinosaurs. Even in the Devonian Period, rather meekly known as the Age of Fishes, terrors were lurking.

The fossil was recently discovered at the Tiktaalik site on Ellesmere Island, part of Canada's Nunavut Territory, by a team of paleontologists at the Academy of Natural Sciences in Philadelphia, as well as the University of Chicago and Harvard.

Laccognathus embryi is most closely related to the modern lungfish, even if it its size is on a whole other order of magnitude. Its size probably ranged from five to six feet long. By the standards of the Devonian Period, that isn't that huge - consider Dunkleosteus, a giant armored fish that measured more than 30 feet long.

But that doesn't mean Laccognathus - which means "pitted jaw" - wasn't a formidable opponent. Thanks to this and previous fossil discoveries, we know that its range extended from what is now Eastern Europe to Northern Canada. Researchers believe was once a linked, sub-tropical ecosystem quite unlike what we see today. Throughout these waters, Laccognathus was content to wait in the ocean depths for easy prey to come its way, at which point its huge, piercing teeth and super-strong jaws would get acquainted with some unfortunate fish.

Dr. Ted Daeschler of the Academy of Natural Sciences explains:

"I wouldn't want to be wading or swimming in waters where this animal lurked. Clearly these Late Devonian ecosystems were vicious places, and Laccognathus filled the niche of a large, bottom-dwelling, sit-and-wait predator with a powerful bite."

Via CBS Philly. Image by Jason Poole/ANSP.