Australia: The Land Where Time Began

A biography of the Australian continent 

Late Cretaceous Crocodiles

There is not much crocodile material known from the Upper Cretaceous of Australia, consisting of isolated teeth, limb bones, vertebrae and scutes. The Winton Formation is the only deposit from which it is known in Australia. In this site a partial skeleton that was well preserved has been found near Isisford, Queensland, that has been attributed to Isisfordia duncani, a small-bodied animal that grew to about 1 m. Isisfordia has reduced back armour, that is unusual, and the skull and vertebrae are of an advanced structure, suggesting that the lateral flexibility was increased  for efficient swimming and structural reinforcement of the cranium to allow it to tackle large prey. Based on these distinctive features Isisfordia is considered to be one of the most primitive members of the Eusuchia, the modern group that includes the gavials, alligators and crocodiles. The authors³ suggest that advanced crocodilians appear to have undertaken part of their evolution in the Gondwanan region. They also suggests that their later successful radiation may have resulted from a major shift of behaviour, such as feeding and/or locomotion.

 

Triassic Australia

Jurassic Australia

Cretaceous Australia