A 165-million-year-old ankylosaur from the Atlas Mountains of Morocco was covered in an array of extreme armour including body spikes fused to its skeleton, a feature never seen in any dinosaur before
By James Woodford
27 August 2025
A life reconstruction of Spicomellus afer, an ankylosaur fossil discovered in Morocco
Matthew Dempsey
A dinosaur fossil found in Morocco may be the most bizarrely and elaborately armoured vertebrate that has ever walked the planet.
The first fossil of Spicomellus afer was discovered in Morocco and reported in 2021. It was only a rib fragment with fused spikes, suggesting that it belonged to a group of dinosaurs known as ankylosaurs. These short-limbed, wide-bodied herbivorous dinosaurs are characterised by their covering of plates and spines.
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Then, in October 2022, a farmer in the badlands of Morocco’s Middle Atlas mountains began to excavate a much more complete Spicomellus skeleton. That fossil has now been dated to 165 million years ago, in the Jurassic Period. The creature was probably about 4 metres long and weighed up to 2 tonnes.
Armoured dinosaurs such as stegosaurs and ankylosaurs, like modern crocodiles, had bony plates that sat in the skin called osteoderms. But in the Spicomellus fossil, there are two different types of bony armour: osteoderms and spikes that are actually fused to the bone.
“It’s unheard of among armoured dinosaurs, and indeed anything that has osteoderms, which is totally crazy,” says Susannah Maidment at the Natural History Museum in London, a member of the team that analysed the fossil.