Scientists describe the 'weirdest' dinosaur ever discovered

(CN) — The world’s “weirdest” dinosaur is even stranger than previously thought, according to new research.

Spicomellus afer, a heavily armored, plant-eating dinosaur called an ankylosaur, had a tail club — a bony weapon at the tip of its tail — long before any other dinosaur in its group. It also had a collar of spikes sticking out from its neck, each about three feet long.

Published Wednesday in Nature, researchers detail just how unusual this species was. It lived more than 165 million years ago during the Middle Jurassic near what is now Boulemane, Morocco.

Fossil remains studied by Susannah Maidment of the Natural History Museum in London, and Richard Butler of the University of Birmingham show that Spicomellus had spikes fused to its ribs and a bony collar around its neck. These features are unlike those of any other vertebrate, living or extinct.

“Spicomellus had a diversity of plates and spikes extending from all over its body, including meter-long neck spikes, huge spikes over the hips, and blade-like spikes along its shoulders,” Maidment said in a press release. “We’ve never seen anything like this in any animal before.”

According to researchers, the dinosaur is also the oldest known ankylosaur, making its elaborate armor even more surprising.

Later species of ankylosaurs, which lived during the Cretaceous period, had simpler armor that probably served mainly for defense.

But researchers say Spicomellus may have used its spikes to show off to rivals or attract mates. Some of its tail bones suggest it had a club or similar weapon, a feature not seen in ankylosaurs until around 30 million years later.

“Seeing and studying the Spicomellus fossils for the first time was spine-tingling,” Butler said in the press release. “We just couldn’t believe how weird it was and how unlike any other dinosaur, or indeed any other animal we know of, alive or extinct.”**

The original description of Spicomellus, published in 2021, was based on a single rib bone.

Researchers say the new partial skeleton, discovered in the same Atlas Mountains rocks, confirms that the species had an unusual body plan. It includes six rib bones with spikes, a bony collar with plates and two pairs of spikes — one of which measures 34 inches — and a pelvic shield with long and short spikes.

The tail vertebrae are fused in a way typical of ankylosaurs with a tail club, indicating the species already had adaptations for both offence and defense.

Researchers say the combination of a tail weapon and an armored shield around the hips suggests that many key ankylosaur features were already in place by the Middle Jurassic.

They also highlight the importance of African fossils in understanding dinosaur evolution. Spicomellus is the first ankylosaur known from the African continent, and its unusual features reveal how much more there is to learn about early members of this group.

“This study is helping to drive forward Moroccan science,” said Driss Ouarhache, who led the Moroccan team at the Université Sidi Mohamed Ben Abdellah, in the press release. “We’ve never seen dinosaurs like this before, and there’s still a lot more this region has to offer.”

The fossils were cleaned and prepared at the Department of Geology of the Dhar El Mahraz Faculty of Sciences in Fez, Morocco, with support from the University of Birmingham. They are now catalogued and stored at the Fez facility.

“To find such elaborate armor in an early ankylosaur changes our understanding of how these dinosaurs evolved,” Maidment said. “It shows just how significant Africa’s dinosaurs are, and how important it is to improve our understanding of them.”