In Depth
It is hard to currently establish a size estimate for Arcusaurus because at the time of writing the genus is only represented by the partial remains of two juveniles. Not only does this make it impossible to run a tape measure along a known complete specimen, but as juvenile they would have grown larger still, to what extent we can’t currently say.
There is also some confusion about how Arcusaurus is related to other sauropodomorphs. A phylogenetic analysis done at the time of the original description found Arcusaurus to be closely related to the genus Efraasia, yet Arcusaurus also possesses certain features that are more common to the later and more advanced sauropodomorphs. It may be that Arcusaurus represents a transitional form of sauropodomorph that links the sauropodomorphs of the late Triassic and early/mid Jurassic.
Further Reading
- A new basal sauropodomorph dinosaur from the Early Jurassic of South Africa - Adam Yates, Matthew Bonnan & Johann Neveling - 2011.
