A colossal fossil! Big-boned new Stegosaurus joins lineup at American Museum of Natural History

No bones about it! A 150-million-year-old fossil has officially joined the American Museum on Natural History.

Known as Apex, the fossil is thought to be the largest and one of the most complete Stegosaurus specimens ever found. The dino will officially go on display among the museum’s fossilized dinosaur skeletons on Dec. 8.

“We are thrilled to have Apex on view at the Museum and grateful to Ken Griffin for his commitment to sharing this magnificent specimen with the public and for partnering with our Museum to do so,” said Sean M. Decatur, president of the American Museum of Natural History. “Mr. Griffin brings a strong sense of civic responsibility, a deep love of and support for science, and an understanding of the power of museums, including ours, to inspire wonder and spur innovation. This partnership allows Apex to have pride of place at a museum world-renowned for its dinosaur collection and for its longstanding leadership in paleontology and, even more exciting, enables us to pursue specialized Stegosaurus research centered around this extraordinary and scientifically important specimen. We hope our millions of visitors are as awe-struck as we are by Apex and look forward to the research breakthroughs ahead.”

Apex was first discovered in May 2022 by commercial paleontologist Jason Cooper in the Morrison Formation just outside of the town of Dinosaur, CO. The specimen measures 11.5 feet tall and 27 feet long and is nearly 80 percent complete, and was prepared and articulated into a defensive pose.

It is also believed that the Stegosaurus is one of the few specimens found that appears to have lived to an advanced age.

The Apex Stegosaurus on view in the American Museum of Natural History’s Richard Gilder Center for Science, Education, and Innovation.Alvaro Keding & Daniel Kim/© AMNH

The colossal fossil was purchased by Kenneth C. Griffin, founder and CEO of Citadel and founder of Griffin Catalyst, at auction from Sotheby’s over the summer, after which Griffin announced that he intended to loan it to a U.S. institution.

“Apex offers a unique window into our planet’s distant past, and I’m so pleased to partner with the American Museum of Natural History to showcase it at one of our country’s preeminent scientific institutions. I am grateful that millions of visitors and researchers will now be able to see and learn from this magnificent specimen of the Late Jurassic Period,” said Griffin. “The joy and awe every child feels coloring a Stegosaurus with their crayons will now be brought to life for the millions of people who have the opportunity to see this epic dinosaur in person.”

During Apex’s museum stay, Griffin will help support the study of Apex as a part of a new research initiative from the Museum’s Division of Paleontology focusing specifically on Stegosaurus biology. There will also be programming around Apex designed for age groups ranging from early childhood to youth, as well as resources for educators and lifelong learners.

The Apex Stegosaurus skull.Alvaro Keding & Daniel Kim/© AMNH

“As exciting as is it is to have this dinosaur on display, it is even more exciting to have the opportunity to study it and make important scientific data available for research,” said Roger Benson, the Museum’s Macaulay Curator of Paleontology and curator-in-charge of fossil amphibians, reptiles, and birds and fossil plants. “Stegosaurus is one of the top dinosaurs known by the general public, but scientifically, we have much more to learn.”

The Stegosaurus will first be on display in the windowed alcove directly to the right of the entrance to the Gilder Center, and in fall 2025 it will join the rest of the fossils on the museum’s fourth floor. It is expected to stay on display at the museum for the next four years, after which a cast of Apex will take the place of the fossil.

For more information on the American Museum of Natural History, visit amnh.org.