Incredible Fossils Shed Light On Mysterious Sharks That Lived 360 Million Years Ago

During the Devonian era, mysterious with bizarre and sinuous bodies swam the seas. Until , we’ve only known about them from teeth and fin spines, but researchers have uncovered skeletal remains in , shedding on what these strange toothy fishes were like.

Describing their finds in the Proceedings of the Royal Society B, the researchers uncovered near-complete skeletal remains, including several skulls, from two different species belonging to the genus Phoebodus. Shark skeletons are notoriously tricky to stumble upon because they are made out of cartilage, not bone.

“It is hard to find shark skeletons of this completeness and quality because they are made out of cartilage,” Frey, of the Palaeontologocial Institute and at the , told IFLScience. “Cartilage is not that robust such as bone and therefore, it is less often preserved. For this , we were overwhelmed by making such a .

“Although the shark Phoebodus was known from plenty of teeth material for decades, skeletons were completely absent before our recent discoveries.” Cartilaginous are known as Chondrichthyes and sharks, skates, and rays.

The remains were found in the Maïder region of Morocco, an area known for its Drotops trilobite . Once a shallow , the sharks lived during the Late Devonian, a period spanning 376 to 360 million years ago that preceded the Carboniferous period. Poor circulation would have helped to preserve the sharks’ bodies by creating a low- .

One of the most notable features of this group of sharks hinted at by the remains is that they had anguilliform – or eel-like – bodies, in addition to a jaw and nose. The physical characteristics of the genus suggest it is closely related to a species of elasmobranch called Thrinacodus gracia, discovered in limestone in , that lived during the Carboniferous era.

Christian Klug
a) reconstruction of a Phoebodus shark b) reconstruction of T. gracia c) of a frilled shark. Linda Frey and , Paläontologisches Institut und Museum, University of

The researchers note that Phoebodus is reminiscent of another shark, but less in terms of relatedness and more in terms of looks. The frilled shark (Chlamydoselachus anguineus) is a living species of shark found in both the and Pacific . A strange creature, it has an eel-like body and slightly --esque teeth arranged in neatly separated rows, each with three spikes.

The bizarre frilled shark. 

Well-known sharks like the great white chomp up their prey, but frilled sharks use a different approach. Their sets of teeth allow them to onto prey and then swallow it whole, with inward-pointing gnashers preventing any unlucky fish that finds its way into the shark’s mouth from escaping.

CT scans of the new fossils suggest that Phoebodus have in a similar way to frilled sharks as both their teeth and body shapes are remarkably similar. The also thinks that Phoebodus’ feeding technique may similarities with that of the alligator gar (Atractosteus spatula), one of the biggest freshwater fishes in , which has a long, flat, almost crocodilian snout that helps it grab fish that appear at its .

first author
A rather sweet-looking alligator gar. Wikimedia Commons

New finds might tell us more about the and of ancient Phoebodus sharks, but for now, we have the most complete skeleton of one of these marine beasts ever uncovered, and that’s pretty .

[H/T: NatGeo]



Related posts