Spicomellus: World’s Oldest Ankylosaur with Meter-Long Neck Spikes and Unprecedented Rib-Fused Armor Discovered in Morocco

In a landmark paper published in Nature on August 27, 2025, an international team led by Dr. Susannah Maidment (Natural History Museum, London, and University of Birmingham) and Professor Richard Butler (University of Birmingham) has unveiled dramatically more complete fossils of Spicomellus afer. The new material — recovered from the Middle Jurᴀssic (~165 million years old) El Mers III Formation near Boulemane in Morocco’s Middle Atlas Mountains — confirms Spicomellus as both the oldest definitive ankylosaur and the first ever found in Africa.

What sets this dinosaur apart is its truly bizarre armor, unlike anything seen in the vertebrate fossil record. Large bony spikes are fused directly to the ribs, emerging through the skin as formidable defensive weapons. It also possessed a mᴀssive bony collar ringed with spikes up to one meter long projecting sideways from the neck, blade-like osteoderms along its flanks, a sacral shield over the hips, and specialized “handle” vertebrae on the tail indicating an early tail weapon — pushing the origin of ankylosaurian tail clubs back more than 30 million years.

“This is jaw-droppingly weird,” said Maidment. “To find such elaborate, extreme armor in the oldest ankylosaur completely changes how we understand the evolution of these animals. It suggests they started with over-engineered defense and display structures that were later simplified in Cretaceous forms.”

At roughly four meters long and two tonnes, Spicomellus was a relatively small but heavily fortified herbivore in a landscape dominated by megalosaurid theropods. Its unique osteoderm-rib fusion represents an independent evolutionary experiment not seen in Laurasian ankylosaurs, highlighting greater diversity and earlier origins of the group in Gondwana than previously suspected.

The discovery demolishes the long-held view that sophisticated ankylosaurian armor only appeared in the Late Jurᴀssic or Cretaceous. Instead, these “walking tanks” were already experimenting with extravagant defensive and display adaptations deep in the Middle Jurᴀssic of North Africa. After the 2021 initial description from a single rib, the 2025 finds provide the definitive proof: Spicomellus was one of the strangest dinosaurs ever to walk the Earth.

Morocco’s Atlas Mountains have once again delivered a revolutionary specimen, forcing paleontologists to redraw the early history of armored dinosaurs. The age of the “spiky collar” has begun.