A mounted Mosasaur (Platecarpus ictericus) skull, late Cretaceous Period, Niobrara Formation, Kansas, mounted on a black enamelled metal stand, within a glazed display case. skull 47 x 46 x 25 cm, glazed case 55.5 cm high, 60 cm wide, 39.5 cm deep, plinth 100 x 66 x 45.5 cm. Accompanied by a letter from Russell Crowe stating his ownership. Provenance: Mr Leonardo DiCaprio, Los Angeles. Mr Russell Crowe, Sydney, acquired from the above, December 2008. The fossil relative of the monitor lizard family, which includes the Komodo Drago, the Mosasaur was a giant, serpentine marine reptile, which was prevalent during the Late Cretaceous Period, approximately 65 million years ago. Mosasaurs were formidable hunters, with a double-hinged jaw and a flexible skull enabling them to eat their prey whole. The Niobrara Formation is a geologic formation located in North America that was deposited between 87 and 82 million years ago.