Alberta mine worker stumbles upon rare fossil of prehistoric marine reptile

The 75-million-year-old fossil of a mosasaur, (MO-sa-sore) an extinct, flipper-bearing prehistoric marine reptile, was discovered at the Korite Mine near Lethbridge on February 16, 2012. Staff from the Royal Tyrrell Museum, led by palaeontologist Dr. Donald Henderson, are currently at the mine working on removal of the fossil.

Paleontologists in southern Alberta are digging up the fossil remains of a marine reptile that could shed light on creatures that roamed Earth as many as 75 million years ago. 

"I saw a kind of cylindrical piece fall out of the side... I went to pick it up, and it had the ridge on it that you would find on a vertebrae," says Jordan Petherbridge, a worker at the Korite Mine near Lethbridge, Alberta, which is southeast of Calgary, who stumbled upon the remains.

Petherbridge was mining for a rare Alberta gem stone last month when he dug up something even more rare. "I was like 'Holy crap!'... this is definitely a bone for sure."

Dr. Donald Henderson, an archaeologist at the Royal Tyrrell Museum in Drumheller, Alberta, says, "We saw the end of the tail, and we knew right away that that was a mosasaur - a type of large, sea-going lizard."

"Dinosaurs were one kind of reptile, (but) mosasaurs are another kind. These things were living in the sea, the same time dinosaurs were living on land."

This lizard is not the type you'd want to mess with. Henderson says, "These things were the top predator in the sea, at the time."

The mosasaur was "the equivalent of the Tyrannosaurus rex of the sea. It had a very big head, with very big teeth, and it was designed for attacking, tearing apart and swallowing big chunks of flesh," Henderson adds.

"Mosasaurs are found all over the world... I think they were a very successful animal."

At first, paleontologists thought they had only found a tail. But they soon discovered what they unearthed was so much more. Mark Mitchell says, "This is excellent. An absolutely beautiful specimen. We have a nice skull...and pretty much a complete skeleton."

The specimen measures six to seven metres long, but Henderson thought there would be more. "We were expecting a much bigger animal, because we saw bones...from about the base of the tail. And we thought, 'Wow, this is going to be a monster' and we thought (it would be) about eight metres long. And then just about two metres further... Oops... we bumped into the the head."

"The preservation is great. The detail on the bone with this fine material is amazing."

Not only was the skeleton nearly complete, but it was unlike any other mosasaur known to have ruled the waters, that covered southern Alberta more than 70 million years ago.

Not a bad find for Petherbridge, an accidental archaeologist. "This is my first one, so it was pretty cool."

Once the skeleton is removed from its marine shale tomb, it will be taken back to the Royal Tyrrell Museum to be studied.