Giant marine reptiles

Between 110 and 98 Million years ago, in the Early Cretaceous Period, inland seas covered much of outback Queensland. In the shallow seas lived a wide variety of marine creatures including fishes, turtles, squid, ammonites and marine reptiles.

The largest and most ferocious of these marine reptiles was the large pliosaur Kronosaurus queenslandicus. It grew in excess of ten metres long. It was a top predator and fed on turtles and other marine reptiles.

The large ichthyosaur Platypterygius was a dolphin-like animal which grew up to seven metres long. It hunted fishes and squids in the shallow seas.

A variety of plesiosaurs and pliosaurs lived in the inland seas during the Early Cretaceous Period.  There are a number of different species of long-necked elasmosaurs known from the Great Artesian Basin. Few have been formally named because the specimens are incomplete. Eromangasaurus is one of the few scientifically named species. Other specimens are given informal names such as “Dave the plesiosaur”. A number of plesiosaur specimens were given the name Woolungasaurus. This name is based on incomplete material and its use has discontinued.

An exceptionally well preserved specimen of polycotylid pliosaur was collected by the Queensland Museum in 1990. This complete specimen is known as the Richmond Pliosaur.

Fossil turtles are also common in the marine rocks of western Queensland. These include the turtles Notochelone and Bouliachelys, which grew to just over a metre long and strongly resembled modern green turtles. Rare fragments of a giant turtle Cratochelone were found in 1915, but no other specimens of this huge animal have been found.

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