Armored Ankylosaurus Dinosaur While primarily recognized in late Cretaceous ecosystems of the Northern Hemisphere, the early evolution of ankylosaurs during the medium Jurassic era remains largely enigmatic due to sparse fossil evidence. Spicomellus Afer has been proposed as the oldest known ankylosaurus and the first discovered in Africa, though this was based on only partial ribs from the Jurassic deposits of central Morocco. Currently, paleontologists are working on a new, better-preserved specimen that affirms the relationship of this ankylosaurus with its relatives and reveals that, unlike contemporary or extinct vertebrates, it features uniquely sophisticated dermal armor.

Spicomellus Afer inhabited Morocco during the mid-Jurassic period, approximately 168 million years ago.

The species was first described in 2021 based on a single fossilized rib.

“In studying spicomellus,” said Professor Richard Butler from the University of Birmingham:

“We were astonished by its uniqueness and how it differed from other dinosaurs and surviving or extinct life forms.”

“This finding challenges our previous understanding of ankylosaurs, indicating how much more we have yet to discover about dinosaur evolution.”

Professor Butler and his team identified that Spicomellus Afer had fused bone spikes that extended over all the ribs—a feature not seen in either living or extinct vertebrates.

These ancient spikes measured up to 87 cm, and it is believed they could grow longer throughout the animal’s life, emerging from a bony collar around its neck.

“The presence of such advanced armor in early ankylosaurs alters our perceptions of their evolutionary trajectory,” remarked Professor Susanna Maidment, a paleontologist at the Museum of Natural History in London and the University of Birmingham.

“This underscores the significance of African dinosaurs and highlights the necessity to further explore them.”

“spiccomellus showcased various plates and spikes extending from its entire body, including meter-long neck spikes, large protruding spikes at the waist, elongated blade-like spikes, paired long spikes for armor, and plates situated beneath the shoulders.”

“We have never encountered anything quite like this in the fossil record.”

“This is particularly intriguing considering that it is the earliest known ankylosaurus. Although later species might have inherited similar characteristics, we should not assume this was the case.”

Researchers speculate that these spikes may have served as displays to attract mates and deter rivals.

Interestingly, no comparable display armor has been identified in other ankylosaurs; the armor in later species likely evolved to be more functional for defense.

One reason for this may be the evolution of larger predatory dinosaurs during the Cretaceous, alongside the emergence of carnivorous mammals, crocodiles, and snakes, leading to a greater need for defensive adaptations among ankylosaurs.

However, one trait that early ankylosaurs might retain is their tail weaponry.

Though the tail of spiccomellus was not recovered, existing bone fragments suggest the presence of club-like structures. Part of the tail vertebrae is fused, forming what is known as a “handle,” a feature only seen in ankylosaurs with tail clubs.

Nevertheless, these latter animals thrived millions of years later in the Cretaceous.

The combination of tail weapons and armored shields indicates that key adaptations seen in ankylosaurs were already present in spicomellus.

This discovery highlights the importance of fossil records in unraveling evolutionary mysteries and enhancing our understanding of dinosaur distribution.

It also ignites the imagination surrounding the dinosaurs like spicomellus.

“This research has significantly advanced Moroccan paleontology,” remarked Professor Doris Oahatch, a paleontologist at Sidi Mohamed Ben Abdela University.

“I have never encountered a dinosaur quite like this. There is still so much to uncover in this field.”

A study detailing this discovery was published in the journal Nature today.

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Scr Maidment et al. The world’s oldest Ankylosaurus armor. Nature Published online on August 27th, 2025. doi:10.1038/s41586-025-09453-6