New fossil shark species discovered in Morocco reveals unique teeth evolution

Saturday 29 November 2025 - 10:20

By: Dakir Madiha

New fossil shark species discovered in Morocco reveals unique teeth evolution

A team of paleontologists has announced the discovery of a new extinct shark species, Pseudocorax heteroserratus, from Morocco’s phosphate beds. This species, identified by its distinctive teeth, offers new insights into shark evolution during the Cretaceous period.

A remarkable find in Morocco’s phosphate beds

The discovery was made in the Oulad Abdoun Basin, near Oued Zem in Khouribga Province, an area renowned for its rich fossil deposits. Researchers unearthed dozens of fossilized teeth from the Couche III layer, a geological stratum formed just before the asteroid impact that ended the age of dinosaurs.

The teeth of Pseudocorax heteroserratus are unique, displaying a mix of smooth, finely serrated, and coarsely serrated edges, sometimes within the same jaw position. This variability sets the species apart from others in the genus and raises intriguing questions about the evolution of serrations in sharks.

A window into ancient seas

The phosphate deposits of the Oulad Abdoun Basin, located about 150 kilometers south of Rabat, contain fossils of marine life that thrived in shallow, warm seas near the end of the Cretaceous. Alongside shark teeth, the region has yielded remains of mosasaurs, plesiosaurs, crocodilians, marine turtles, and even rare dinosaurs, painting a vivid picture of a diverse prehistoric ecosystem.

The new species belongs to the mackerel-shark order (Lamniformes) and is the first since Pseudocorax affinis to be recognized for serrated tooth edges. However, the irregularity of these serrations in Pseudocorax heteroserratus suggests a more complex evolutionary pathway.

Evolutionary significance

The unique teeth of Pseudocorax heteroserratus challenge paleontologists to reconsider the development of serrations in shark lineages. Two possibilities are proposed: serrations may have evolved independently in different populations, or they could have emerged once and spread unevenly among species.

The study also links the extinction event at the Cretaceous-Paleogene (K–Pg) boundary to this evolutionary puzzle. The asteroid impact that wiped out the dinosaurs may have disrupted the ecological pressures shaping the development of serrations in Pseudocorax heteroserratus.

The importance of Morocco’s phosphate beds

Morocco’s phosphate mines continue to be a treasure trove for paleontology, providing unparalleled insights into life before the mass extinction. The discovery of Pseudocorax heteroserratus not only expands the shark family tree but also highlights the need for large fossil samples to better understand species variations and evolutionary adaptations.

This remarkable find underscores the global significance of Morocco’s fossil heritage and the evolutionary stories hidden within its phosphate beds.