Ichthyosaurs of the Toolebuc Formation
The ichthyosaurs of the Toolebuc Formation are represented by a single species. Platypterygius australis, which grew to more than five metres.
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
Platypterygius had a streamlined body to reduce drag, and, like most ichthyosaurs, it had enormous eyes, among the largest recorded for any animal.
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
The size of its eye suggests Platypterygius relied on sight to hunt its prey. Bony, sclerotic plate around each eye may have prevented them from being distorted by water pressure when the animal was diving.
The genus Platypterygius is the last record of ichthyosaurs worldwide. The youngest known specimen from Australia, which are dated at about 90 million years, come from mudstones near Darwin in the Northern Territory. Ichthyosaurs had already diminished in number by the start of Early Cretaceous, but their extinction may have been hastened by changing global sea levels and reduced genetic variety.
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
Platypterygius australis Platypterygius australis (1932) by Peter Waddington, Queensland MuseumQueensland Museum Network
Images and text from: In Search of Ancient Queensland.
Principle Authors: Dr Alex Cook and Dr Andrew Rozefelds.
Published by the Queensland Museum, 2015.
Photographer: Peter Waddington
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