First found in 1964, there are now over 5 Minmi specimens known, including an almost complete skeleton that was unearthed in 1987 that was possibly mummified (there are even reports of Minmi fossils being found in Victoria and even New Zealand ).

Found in Roma, Queensland and named after a nearby creek (the Minmi crossing), Minmi is unusual for several reasons, including being the first thyreophoran unearthed in the Southern Hemisphere and is also one of the few dinosaurs that are known from an almost complete specimen.

It was originally thought to be a nodosaur- an early, primitive group of ankylosaurs, thanks to its small size and club-less tail. Minmi was then pushed into the ankylosaur family when an apparent club was recognised on the tail of one specimen. This ‘club' has since turned out to be a nothing more then a stone concretion, so Minmi may end back in the nodosaur family. What is more likely however thanks to its mix of advanced and basal (primitive) features is that Minmi is one of the first ankylosaurs.

The second Minmi found and the most complete one known was found with several marine fossils including an ammonite, mussel shells and the teeth of a shark called Echinorihnus , all strong evidence that this dinosaur was washed out to sea near the time of, or after its death, also it's missing feet may indicate that the carcass was partly scavenged by these sharks (though there's no real evidence of this).

What is apparent though is that the body was mostly complete before being buried, as part of the animal's chest seems to have ruptured from within, a sure sign of a corpse bloating from the expansion of inner gases. An incomplete corpse will often allow these gases to escape from its wounds. Many of the bony ‘scutes' that make up thyreophoran armour (stegosaurs and ankylosaurs) have also been found in roughly the position you'd expect to find them in during life. This is highly suggestive that they were still buried within the dinosaurs' skin when it died and came to rest in its finally burial place. If the animal had been scavenged, you would expect to find removed, destroyed or simply missing pieces from being eaten, pushed aside, or bitten away and removed o allow access into the soft flesh underneath.

The most complete specimen (QM F18101) and the first (QM F10329) are important finds for many, many reasons. Firstly Australia 's dinosaur fossil record is poor, with very few good remains having been unearthed in the last century or more, so to find a near complete skeleton is more then a little exciting for Australian palaeontology. But there is much, much more than just that about Minmi.

A close study of this ankylosaur's skull shows it has several basal features of all ankylosaurs, including a ‘box' shaped skull, which also held some primitive thyreophoran features (like the basal Scelidosaurus ), such as its skull being longer than it is wide, and similar patterns of the armoured scutes on its skull to these basal thyreophorans. This may be important, as it's never truly been decided if the Jurassic's herbivores such as Scelidosaurus gave rise to the stegosaurs, and then the ankylosaurs or just the ankylosaurs. If a seemingly basal ankylosaur like Minmi shares many Scelidosaurus features, then it may well be the latter.

Again, as important as this is, there is still much more about this unassuming little dinosaur that is of great importance.

The full name for Minmi is M. paravertebra pointing out the unusualness of Minmi's spine when viewed against all other dinosaur species. Minmi's vertebrae are unique, as they possess bony extensions called paravertebrae. These would have given support for the heavy plates of armour that crisscrossed Minmi's back, head, neck tail and even its stomach. This support may have even made Minmi quiet fast in the ranks of the thyreophorans.

The diet of dinosaurs is often ‘suggested' by either studying their teeth shape and size or by the examination of trace evidence such as coprolites (dinosaur poo), teeth marks on bones (in the case of carnivores such as tyrannosaur bites on hadrosaurs and ceratopsian remains…as well as each other). Even rarer (and yet more direct evidence) are the remains of dinosaur stomach contents called Cololites. Though several claims of stomach remains have been made over the years, very few have ever been accepted as fact. Often the skeletons (just like Minmi ) are found in marine or fresh water deposits where some believe these strange remains may just be debris that has been washed into the exposed cavity of the carcass's chest (many of these possible Cololites are also full of things like sand, which an animal is unlikely to eat).

While preparing the 1989 specimen a small 30mm by 43 mm ‘smear' was exposed that seemed to show the remains of the ankylosaurs last meal. Where many other ‘stomach' contents seem to contain plants along with other improbable debris such as sand (all of which could have been ‘washed' in), the ‘smear' in Minmi is a little different. This is made up of plants that are uniformly the same size, with many of the pieces (that would have been part of a bigger plant or leaf) showing sharp edges that suggest the pieces were bitten or chewed. The regularity of the pieces also seems to point to the dinosaur eating favoured plants rather than just grazing at anything in front of its mouth.

Many of the leaves still show vascular structures, while there are a few pieces that are reminiscent of seed bearing fruits like berries. This makes a lot of sense as these, along with plants that have been cut into small pieces, are more susceptible to digestion by stomach acids. The larger the surface area the faster something will break down, thus by cutting plants into smaller pieces these dinosaurs were making the surface area of their meal larger, in turn making them easier to digest. This simple process also makes gastroliths or ‘stomach stones' less important to an animal- which seems to be the case as there is no evidence of these inside Minmi's stomach.

This may not mean anything however. The position of the smear and its size strongly suggest that it's not actually from the stomach (which would be holding gastroliths), but instead is part of the stomach tract, which would not have any stones in it unless they were in the process of being swallowed. The position of the smear however could be confusing as the animal seems to have been buried upside down and the stomach could easily have been ‘pushed' into this strange position by expanding gases within the body.

Australia itself was very different to the continent we know today. During the cretaceous that Minmi lived in, the worlds largest island was mostly covered by a shallow, warm sea that were full of dangerous predators like the elasmosaur called Woolungosaurus , sharks and one of the worlds largest ever marine reptiles, Kronosaurus .

Scattered throughout these waters were islands both large and small, making Australia look more like the chain of islands called the Philippines . It's on these pockets of life that these small ankylosaurs would have lived their lives, and it's because of this environment that so many of these northern Australian fossils are found in marine sediments.