Image: Minmi paravertebra
Ilustration of Minmi paravertebra. This illustration was based on the most complete specimen found at Marathon Station, near Richmond in north-western Queensland. A replica can be seen in the Australian Museum's Dinosaurs Exhibition.
- Dr Anne Musser
- © Dr Anne Musser
What was Minmi?
Minmi paravertebra was a 3 metre long ankylosaur that was discovered in 1964 near Minmi Crossing, Queensland. Minmi was the first ankylosaur known from the Southern Hemisphere.
What did Minmi look like?
Ankylosaurs were heavy plant-eating dinosaurs that walked on all fours. They were armoured for protection against predators.
Minmi was unique in having small, bony projections (paravertebrae) along the backbone. These faced backwards and provided extra attachment for back muscles. These paravertebrae were similar to the bony structures found in today's crocodiles that strengthen and support the back during the 'high walk'. This allows the crocodiles to lift their body clear of the ground to get over obstacles like rocks or logs and also allows them to run fast for short distances. This means that Minmi could have outrun some predators rather than just relying on its armour for protection. Minmi's unusually long legs would have also helped.
Minmi also had:
- belly armour (absent in most ankylosaurs and related stegosaurs)
- neck and trunk armour (scutes, spikes and dermal ossicles)
Minmi did not have a clubbed tail. It also had no dermal (under the skin) armour on the skull, unlike almost all other ankylosaurs.
What was Australia like when Minmi was alive?
During the Early Cretaceous, part of Queensland formed a large island separate from the rest of Australia. There was a mixture of floodplains and woodlands.
Although the original fossil of Minmi was found in marine (sea) sediments, it was probably washed out to sea from this nearby terrestrial (land) environment.
What did Minmi eat?
A study of the contents of Minmi's fossilised gut contents found that it ate: seeds, fruit, ferns and other soft plant material.
The plant material found in Minmi's stomach was finely diced. Minmi may have cut its food with its serrated cheek teeth after nipping the vegetation off with its beak.
There were no gastroliths – stones in the stomachs of many plant-eaters that help grind up tough plant matter - suggesting that Minmi's teeth were quite good at chewing food.