A 66 million-year-old skeleton of one of the largest known Tyrannosaurus rex specimens ever discovered will be up for sale at an auction in LasVegas on October 3.

The rare skeleton – dubbed ‘Samson’ – is arguably one of the three most complete specimens to have been discovered, auction house Bonhams said.

Native to North America, Tyrannosaurus rex is recognized as the ‘Tyrant Lizard King’ and is the most famous of the behemoths of the “Age of Dinosaurs.”

This rare example from the Cretaceous period was excavated near Buffalo, South Dakota over 15 years ago.

It is 40 feet long and 15 feet tall and consists of around 170 bones, more than half of a complete skeleton.

The last one of these skeletons to go up for sale, Sue, the most complete specimen ever found, sold for more than $8 million dollars in 1997 to the Chicago Field Museum.

Unlike Sue, which was still in pieces when sold, Samson is fully prepared and mounted and could fetch even more.

The skeleton will be offered by international auctioneers Bonhams & Butterfields on Saturday, October 3, 2009 during the company’s first Natural History auction to be held at The Venetian in Las Vegas.

The specimen will be exhibited and sold in the space formerly occupied by The Guggenheim Hermitage Museum.

In addition to “Samson,” the October 3rd sale will also feature approximately 50 lots of high quality and distinctive dinosaur specimens and exceptional fossils.