Minmi paravertebra or is this Kunbarrasaurus ieversi?

Everything Dinosaur team members were reviewing some of the images from Zhao Chuang within their database and spotted an anomaly.  Zhao Chuang is the talented artist responsible for many scientific illustrations of prehistoric animals including the beautiful images associated with the PNSO “Age of Dinosaurs” range.   One picture of an armoured dinosaur was labelled Minmi, indicating that this was an illustration of Minmi paravertebra.  However, we have seen this image used in articles associated with the naming and scientific description of another Australian member of the clade Ankylosauria – Kunbarrasaurus ieversi.

Is This Minmi or Kunbarrasaurus?

Picture credit: Zhao Chuang

Confusing Minmi paravertebra and Kunbarrasaurus ieversi

Kunbarrasaurus was named and described in 2015.  The fossil remains that led to the erection of this new genus had been formerly described as Minmi (M. paravertebra).   In 1989,  the nearly complete skeleton of an armoured dinosaur was discovered on Marathon Station, near Richmond, north-western Queensland.  The specimen (QM F18101), was provisionally assessed as a specimen of Minmi paravertebra, at the time, the only known armoured dinosaur from Australia.

However, further preparation of the fossil material and a detailed CAT scan of the fossils identified notable differences in skull anatomy when compared to the fossil material that had been ascribed to Minmi paravertebra.  These autapomorphies (different traits), were deemed sufficient to permit the establishment of a new genus of armoured dinosaur and the scientific paper detailing this research was published in the journal PeerJ.

To read Everything Dinosaur’s article on the naming of Kunbarrasaurus from 2015: The Newest Dinosaur from Australia.

The Kunbarrasaurus Fossil Specimen (QM  F18101)

Picture credit: The University of Queensland

How Closely Related is Kunbarrasaurus to Minmi paravertebra?

More than half a dozen fossil specimens have been ascribed to the genus Minmi, however, of these, only two have been studied in detail.  Lack of relative and temporal dating information of the fossil bearing strata in Australia has hindered classification as has the presence of extensive dermal armour which has caused problems when palaeontologists attempt to identify subtle differences in skull morphology and nasal pathways.

Exactly how closely related these two Australian armoured dinosaurs were to each other remains an area of debate amongst scientists.  Minmi has been assigned as a basal member of the  Ankylosauridae, the family of armoured dinosaurs that includes Ankylosaurus and Euoplocephalus.  However, the fossil material ascribed to the genus K. ieversi is regarded by many palaeontologists as sufficiently different that it can’t be placed within the Ankylosauridae family, but it has been assigned to the clade Ankylosauria, a broader group encompassing less closely related animals.

For models and replicas of ankylosaurs and other armoured dinosaurs: CollectA Prehistoric Life Models.

Further revision of the taxonomic relationships between armoured dinosaurs that roamed Gondwana is likely as more fossils are found.  Therefore, it is understandable for the work of a scientific illustrator to become mixed up in the phylogenetic assessments.  Whether Zhao Chuang’s illustration represents Minmi or Kunbarrasaurus is a moot point, it remains a fantastic armoured dinosaur illustration (in our opinion anyway).

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