A group of researchers has discovered in Morocco the fossils of a Spicomellus afer, a strange dinosaur with armor of spikes up to a meter long, details a study in the journal Nature.

The spikes of S. afer, the oldest ankylosaur in the world, protruded from its neck and were fused with its ribs, a feature never before seen in any other vertebrate species—living or extinct.

Rare fossils that helped identify the dinosaur

“We’ve never seen anything like it in any animal,” says researcher Susannah Maidment of London’s Natural History Museum and the University of Birmingham, who acquired a rib from the prehistoric animal in 2019.

Now, a team of paleontologists has found other remains in the Atlas Mountains near the town of Boulemane, Morocco, helping to complete the description of the dinosaur.

A shift in what we know about ankylosaurs

These “absolutely bizarre” fossils were changing how scientists think armored dinosaurs evolved: “When we originally named S. afer, there were doubts that it was actually an ankylosaur,” the expert says.

Now, “not only can we confirm beyond a doubt that this interpretation was correct, but the only known ankylosaur from Africa is much stranger than anyone imagined,” he says.

Characteristics of S. afer

The identified ankylosaur roamed the Earth 165 million years ago. Its fossils revealed that it had 87-centimeter (34-inch) neck spines, which could have been even longer during its lifetime.

“This is an incredibly significant find. It’s one of the strangest dinosaurs we’ve ever discovered. It’s completely unlike anything else you’ll find anywhere else in the world,” says co-author Richard Butler of the University of Birmingham.

Armored Dinosaurs Compared to Tanks

Ankylosaurs were a group of plant-eating dinosaurs known for their armored bodies, sometimes compared to a tank, and for their club-like tail tips.

The discovery of S. afer “is going to teach us a lot about the early evolution of ankylosaurs, which were like tanks,” Butler adds.

Purposes for Their Armor’s Spikes

Scientists aren’t sure what the ancient creature’s spikes did. The caudal vertebrae suggest that it had a weapon at the end of its tail, perhaps a club, to defend itself from predators, although there is no evidence.

Butler believes that this armor, much more complex than that of other ankylosaur species, could be due to a shift to a more defensive function due to the increase in size and numbers of predators in the Cretaceous.

Function related to mating

However, beyond their possible defensive function, it is feasible that these dinosaurs could have used these spikes to attract mates or show off to rivals.

"The armor is totally impractical and would have been a bit of a nuisance in dense vegetation," says Maidment.

In living animals, structures that tend not to have an obvious function and that seem a bit annoying to wear, such as deer antlers, are usually associated with sex, explains the paleontologist.

"Therefore, we believe it is possible that the animal developed such elaborate armor for some kind of display, perhaps related to mating," he concludes.