Giant Primordial Worm With Record-Breaking Jaws Uncovered By Scientists

Published February 27, 2017
Updated December 20, 2017
Published February 27, 2017
Updated December 20, 2017

This extinct creature is actually comparable in size to one worm species that is still alive today.

Websteroprion Armstrongi Giant Worm

James Ormiston

Scientists have recently discovered evidence of a giant primordial worm with humongous snapping jaws that may have haunted the high seas in ancient times. And even more excitingly, its lookalike is still alive today.

An international team of scientists from the University of Bristol, Lund University, and the Royal Ontario Museum have published evidence of the now-extinct oversized bristle worm in Scientific Reports.

As a newly discovered species, the Websteroprion armstrongi is unique in possessing the biggest jaws of any known worm in existence. Most fossil worm teeth are only a few millimeters in size and cannot even be seen with the human eye, while the fangs on this giant worm are more than a centimeter (0.4 inches) in size.

Websteroprion Armstrongi

An artistic reconstruction of Websteroprion armstrongi.

Likewise, even though it is the marine-related ancestor to pint-sized creatures such as earthworms and leeches, this ancient worm is thought to have grown to be almost a yard long.

“Gigantism in animals is an alluring and ecologically important trait, usually associated with advantages and competitive dominance,” said lead author Mats Eriksson in a news release. “It is, however, a poorly understood phenomenon among marine worms and has never before been demonstrated in a fossil species.

“The new species demonstrates a unique case of polychaete gigantism in the Palaeozoic, some 400 million years ago,” Eriksson added.

Furthermore, according to the researchers, the ancient worm is comparable in size to the “giant eunicid” species (colloquially referred to as “Bobbit worms”), which is still alive today:


“[The similarities between the two species] shows that gigantism in jaw-bearing polychaetes was restricted to one particular evolutionary clade within the Eunicida,” said co-author Luke Parry, “and has evolved many times in different species.”

Call it what you want, but it does look terrifying to be that fish above.

Next, check out the mysterious life forms that NASA scientists recently found hibernating inside giant Mexican cave crystals, before finding out about the plan that Harvard scientists have to resurrect a woolly mammoth by 2019.