Australia: The Land Where Time Began

A biography of the Australian continent 

Saurischia - Lizard-hipped dinosaurs`   

Dinosaurs of the order Saurischia have a primitive pelvic bone pattern with a pubis that points forward and an ischium that points rearwards. This is a carry over of the pelvic structure that arose with the ancestral reptiles. It is still present in modern reptiles, such as lizards and crocodiles.

The saurischians share many primitive archosaurian features in common, but it is uncertain whether they all share a common ancestry. The Saurischia are divided into 2 main groups, the Theropoda, carnivorous bipedal animals and the Sauropodomorpha, that include the giant long-necked herbivores with small heads containing simple peg-shaped teeth and a long tail, and related ancestral forms such as prosauropods, e.g., Plateosaurus, Agrosaurus.

Included among the sauropodomorphs are the giants in the groups diplodocoids, brachiosauroids and titanosaurians.

Prosauropodidae

These were mostly dinosaurs with long necks and tails that mainly walked upright on pillar-like legs. In the Triassic this group were large omnivorous dinosaurs, some becoming herbivores and other carnivores. They gave rise to the sauropods that reached their greatest size in the Jurassic.

Agrosaurus macgillvirayi Late Triassic-Early Jurassic Cape York Peninsula, Queensland

• Theropoda
• Sauropodomorpha

Sources & Further reading

1. Long, John A, 1998, Dinosaurs of Australia and New Zealand, University of New South Wales Press.
2. Norman, David, 2005, Dinosaurs: A Very Short Introduction, Oxford University Press