Analysis of an unusual fossil showing a series of barbs fused to a rib reveals that they are remains of the oldest ankylosaur ever found and the first on the African continent.
The discovery was made in the Middle Atlas Mountains of Morocco at the same site where UK NHM (National History Museum) researchers previously discovered the oldest stegosaurus ever found.
The new species was described by Dr Susannah Maidment, NHM Researcher and Honorary Senior Lecturer at the University of Birmingham, and named it Spicomellus afer: Spicomellus meaning “collar of spikes” and afer meaning “from Africa.”
“At first we thought that the specimen could be part of a stegosaurus, as we had previously found it in the same location. But on closer inspection, we realized that the fossil was different from anything we had seen,” he said. it’s a statement.
The specimen is so unusual that researchers initially wondered if it could be a fake. The CT scan showed that it was the real deal, and a cross-section of the base of the specimen showed a cross-hatch pattern in the bone unique to ankylosaurs, revealing their identity.
“Ankylosaurs had armored spines that are generally embedded in their skin and not fused with bone. In this specimen we see a series of spikes attached to the rib, which must have protruded above the skin covered by a layer of something similar to the keratin, “explained Maidment. “It’s unprecedented and unlike anything in the animal kingdom.”
Ankylosaurs were a diverse group of armored dinosaurs related to the more well-known stegosaurs. They were present throughout the Cretaceous period, but there is little evidence of them before then, making this new fossil not only the first ever found in Africa, but also the first example of the group ever discovered.
The new discovery dates to the middle Jurassic period about 168 million years ago. It has helped fill an important gap in our understanding of dinosaur evolution and suggests that ankylosaurs may have had a global distribution.
The discovery also challenges an earlier theory that ankylosaurs outnumbered stegosaurs and led to their extinction. This new finding, however, means that the two groups coexisted for more than 20 million years and implies that the extinction of the stegosaurs may have occurred for other reasons.
The fossil that led to the description of this new species is now part of the NHM collections and will be the subject of ongoing study. The research is published in the journal Nature Ecology & Evolution.