Scientists have discovered a bizarre armoured dinosaur which had metre-long spikes sticking out from its neck. The species, called Spicomellus afer, lived 165 million years ago and is the oldest example of a group of armoured dinosaurs called ankylosaurs. The elaborateness and spikiness of the animal found in Morocco has come as a shock to experts, who now have to rethink how these armoured dinosaurs evolved.

Prof Richard Butler, from the University of Birmingham who co-led the research, told BBC News that it was the punk rocker of its time. Punk rock is a sub-culture and music style that first emerged in the 1970s. Its followers often have spiky hair and accessories.

It is one of the strangest dinosaurs ever discovered, said Prof Butler. Prof Butler's project co-leader, Prof Susannah Maidment of the Natural History Museum, added that it was surprising that the spikes were fused directly on to the bone.

We don't see that in any other animal, living or extinct, she said. It's absolutely covered in really weird spikes and protrusions all over the back of the animal, including a bony collar that wraps around its neck and some sort of weapon on the end of its tail, so a most unusual dinosaur, she said.

The discovery is so unusual that the two professors are considering whether the discovery might force a rethink of theories on how ankylosaurs evolved.

These animals survived late into the time dinosaurs were on Earth, in a period known as the Cretaceous, which spanned from 145 to 66 million years ago. At the end of this period emerged large carnivorous predators, such as T. rex, leading scientists to previously think that ankylosaurs began with simpler armoured plates which evolved to become larger for protection.

The researchers estimate Spicomellus afer would have been about four metres long and one metre high, weighing around two tonnes.