TORONTO.- Scientists from the Royal Ontario Museum have identified and named a new species of anklylosaurid or armoured dinosaur, Zuul crurivastator (Zool CRUR-uh-vass-TATE-or). Its skeleton, acquired by the ROM in 2016, is one of the most complete and best preserved skeletons of this group of dinosaurs ever found, which includes a complete skull and tail club, and preserved soft tissues. Research on the new species is published in the May 10 issue of the open-access journal Royal Society Open Science.

The new 75-million year old, plant-eating dinosaur is named after ‘Zuul’, a fictional monster from the 1984 movie Ghostbusters, based on the features of its well-preserved skull. Like Zuul, the new species has a short, rounded snout and prominent horns behind the eyes. The shape of the horns and the ornaments on the skull are what identified Zuul as a species new to science. Its species name, crurivastator, means ‘destroyer of shins’, and references the incredible weapon-like tail club found with the skeleton. Ankylosaurid ankylosaurs have a large knob of bone at the tip of their stiffened tails, which could have been used to strike at the legs of predatory dinosaurs in defense, or may have been used to battle each other during contests for mates or territory. Notably, the 3 m (10 feet) long tail of Zuul also had many rows of large, sharp bony spikes, in addition to the tail club, making it particularly menacing. Zuul would have been approximately 6 m (20 feet) long and weighed around 2,500 kg (5,500 pounds) about the size of a White Rhinoceros.

"I’ve been working on ankylosaurs for years, and the spikes running all the way down Zuul’s tail were a fantastic surprise to me – like nothing I’ve ever seen in a North American ankylosaur. It was the size and shape of the tail club and tail spikes, combined with the shape of the horns and ornaments on the skull, that confirmed this skeleton was a new species of ankylosaur,” says Dr. Victoria Arbour, the Natural Sciences and Engineering Research Council of Canada (NSERC) postdoctoral fellow at the ROM and University of Toronto, expert on armoured dinosaurs and lead author on this new study.

The new dinosaur discovery is based on a nearly complete skeleton excavated from the Judith River Formation of Montana, where some of the first dinosaurs ever discovered in North America were collected and described. Zuul is not only the first ankylosaurid named from the formation, it is also one of the most complete and best-preserved ankylosaurs ever discovered, with skin impressions preserved on the tail, and the keratin sheaths preserved on some of the armour spikes.

“The preservation of the fossil is truly remarkable. Not only is the skeleton almost completely intact, but large parts of the bony armour in the skin are still in its natural position. Most excitingly, soft tissues such as scales and the horny sheaths of spikes are preserved, which will be a focus of our future research,” said Dr. David Evans, Temerty Chair and Curator of Vertebrate Palaeontology at the Royal Ontario Museum, and leader of the project.

Zuul was found only 25 km from the Alberta border, in badlands along the Milk River. A ROM team led by Dr. David Evans has been working in the same layers of rocks for almost 15 years as part of the Southern Alberta Dinosaur Project. The new ankylosaur, and the other fossils found in the same quarry, contribute to this long-term research project, and help flesh out the evolution of ecosystems during the twilight of the dinosaurs.