Image: Opalised jaw of Steropodon galmani

Opalised jaw of Steropodon galmani

Steropodon galmani Archer. One of Australia's oldest mammal fossils, from the Early Cretaceous rocks at the opal fields of Lightning Ridge, New South Wales.

Carl Bento
© Australian Museum


Steropodon galmani, a platypus-like monotreme from the Early Cretaceous, was the first Mesozoic mammal discovered in Australia. It is known from this opalised lower jaw with molar teeth. The teeth of Steropodon are similar to those of later fossil platypuses although its molars are more archaic in form.Steropodon lived alongside dinosaurs, crocodiles, early birds and other early mammals on the forested shores of the inland Cretaceous Eromanga Sea.

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Tags opalised, fossil, jaw, teeth, tooth, dentition, mammals, monotremes, platypus, Early Cretaceous, Lightning Ridge, NSW,

1 comment

Elanor McCaffery - 4.08 PM, 13 August 2010

Whenever I see this fossil I always think the opalised part on the left looks like a face, especially with that black dot for an eye.

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