The Finest Stegosaurus Specimen Ever to appear at Auction

This summer, Sotheby’s annual Geek Week sale series will feature 'Apex,' the finest Stegosaurus specimen to come to market. Distinguished not only by its remarkable size, measuring 11 feet tall and 20 feet long, this exceptional fossil is virtually complete, and incredibly well preserved. It carries an estimate of $4-6 million, making it one of the most valuable dinosaur fossils ever offered.

The auction on 17 July marks a significant moment, as the first instance of an auction house working to bring a dinosaur specimen to market, starting from the day of its discovery. Sotheby's collaborated closely with the owner to document the entire process, from discovery and excavation to restoration, preparation, and mounting, ensuring that the documentation and sale of the specimen is handled with the highest standards and transparency.

“Apex” not only represents a significant achievement for paleontology but also continues Sotheby’s legacy of pioneering Natural History auctions. After unveiling the inaugural Gorgosaurus skeleton in July 2021 and achieving the landmark sale of the first standalone Tyrannosaurus rex skull with “Maximus” in December 2022, “Apex” marks the latest significant addition to this series, following Sotheby’s groundbreaking 1997 sale of Sue the T. rex, the first-ever dinosaur to be sold at auction.

The Stegosaurus is the best-known of the armored dinosaurs. Photo: Matthew Sherman/Courtesy Sotheby’s

The Stegosaurus is the best-known member of the armored dinosaurs (Thyreophorans), characterized by the distinctive shape and arrangement of dermal armor on its back, extending from the neck to the tail. Fossils of this intriguing group have been found in Jurassic-Cretaceous localities throughout Eurasia, North America, and Africa. In the Morrison Formation, Stegosaurus species are classified into two genera, Stegosaurus and Hesperosaurus. They are primarily differentiated by the shape of their dorsal plates: Stegosaurus plates are taller and pointed, while Hesperosaurus plates are wider and more rounded. Both genera share a set of four spikes at the end of the tail, though Stegosaurus additionally has unique throat (cervical) armor that Hesperosaurus lacks. The taxonomic distinctions between these two genera and their species remain a topic of ongoing debate.

“Apex” was discovered in May 2022 in the Morrison Formation, located in Moffat County, Colorado, near the town of Dinosaur. The excavation was completed in October 2023. The specimen shows no signs of combat or predation-related injuries; however, evidence of arthritis indicates that it lived to an advanced age.

The name "Apex" was chosen to underscore its prominence within the Stegosaurus family, reinforcing the high regard for Stegosaurus among dinosaurs. A comparable fossil, “Sophie” today is held in the collection of the National History Museum in London. “Apex” is more than 30% larger than Sophie, boasting an impressive femur length of 45 inches.

“Apex” was discovered by a well-known and respected commercial paleontologist on his own private land. This paleontologist has unearthed numerous dinosaur specimens within the United States, many of which are housed in institutions around the globe, with a significant number having been donated by him. Believing in "minimal intervention," he meticulously prepared the specimen to the highest standards, showcasing the fossils’ natural beauty and preserving important contextual information, including fossilized skin impressions and cervical ossicles. “Apex” was found alone, with no other fossils nearby, representing a singular specimen as it lived.

Main Image :Photo Credit: Matthew Sherman