SALT LAKE CITY – A newly discovered species of armored lizard, about the size of a raccoon, has been unearthed in the Grand Staircase-Escalante National Monument in southern Utah. The find,named Bolg amondol,provides valuable insights into the diversity of large lizards during the Late Cretaceous period.

The research, a collaborative effort led by the Dinosaur Institute and the Natural History Museum of Utah (NHMU), highlights the potential for future paleontological discoveries within museum fossil collections and protected public lands like the Grand Staircase-Escalante National Monument.

According to experts at the Dinosaur Institute of the Natural History Museum of los Angeles County, this discovery reveals a surprising variety of large lizards that existed alongside dinosaurs.

Named after a character from J.R.R. Tolkien’s “The Hobbit,” Bolg Amondol offers clues about the interconnectedness of life across ancient continents.

Hank Woolley, the lead author from the Dinosaur Institute of the Natural History Museum of Los Angeles County, stated, “We know very little about the large-sized lizards of the Kaiparowits formation, in the Utah national grand-scallant national monument, so I immediately knew that this was important.”

Randy Irmis, co-author, associate professor at the University of Utah, and paleontology curator of the NHMU, added, “Discovering a new species of lizard, ancestor of the modern Gila monsters, is engaging in itself, but the most exciting thing is what reveals us about the unique ecosystem of 76 million years in which he lived. The fact that Bolg coexisted with several other species of large lizards indicates that it was a stable and productive ecosystem where these animals took advantage of a wide variety of dams and different microhabitats.”

bolg Amondol belongs to an evolutionary line within the monstrousaur group of large lizards. Woolley chose the name “Bolg,” a Goblin Prince from “The Hobbit,” due to the lizard’s goblin-like skull. He also used Sindarin, Tolkien’s fictional Elvish language, to create the species epithet “Amondol,” meaning “mound head,” referring to the mound-shaped osteoderms found on the skulls of Bolg and other monstrousaurs.

The Importance of Large Lizard Discoveries

The discovery of Bolg Amondol emphasizes the possibility that large lizards were more prevalent during the Late Cretaceous period than previously thought. Fossils from the Kaiparowits formation indicate that at least three types of predatory lizards inhabited the subtropical alluvial plains of what is now southern Utah. This finding suggests that ther is still much unexplored diversity to be uncovered in both the field and paleontological collections.

“It measured a meter from the tail to the tip, perhaps even larger…something you would not want to put in.” – Hank Woolley

Researchers identified the new species based on fragments of the skull, limbs, waist, vertebrae, and bony armor called osteoderms. Despite the fragmentary nature of the fossils, the surviving parts of the Bolg skeleton contain a wealth of facts.

Woolley explained, “That means we have more characteristics to evaluate them and compare them with similar -looking lizards. It is significant to highlight that we can use those characteristics to understand the evolutionary relationships of this animal and verify hypotheses about its place in the family tree of lizards.”

Monstrosaurs are characterized by their large size, sharp teeth, and polygonal armor. Their fossil record,spanning approximately 100 million years,is incomplete,making the discovery of Bolg Amondol a crucial step in understanding these lizards. To our eyes, Bolg would have appeared monstrous.

“It measured a meter from the tail to the tip,perhaps even larger,depending on the length of the tail and the torso,” says Woolley. “so, for the standards of modern lizards, it is a very large animal, similar in size to a varano of the savannah; something you would not want to put in.”

Asian Connection

the closest known relative of Bolg Amondol lived in the Gobi Desert in Asia.This discovery supports the idea that smaller animals, like dinosaurs, migrated between continents during the Late cretaceous period, indicating shared biogeographic patterns among terrestrial vertebrates.

The Kaiparowits formation within the Grand Staircase-Escalante National Monument has become a key paleontological site over the past 25 years, yielding remarkable dinosaur records. Discoveries like Bolg Amondol underscore the importance of preserving public lands in the western United States for scientific research.

Joe Serich, co-author from the Smithsonian Institute of Tropical Research and the State University of Colorado, noted, “The remarkable registration of large lizards of the Grand Stair-scaling national monument might potentially be to be a normal part of the ecosystems dominated by north-America dinosaurs, fulfilling key functions such as smaller predators that hunt eggs and small animals in the forests of Laramidia.”