Description and Classification

Cedarpelta was a medium-sized, heavily built herbivorous dinosaur. Scientists estimate it grew to be about 5 to 6 meters (16 to 20 feet) long. Like other ankylosaurs, it walked on four sturdy legs and its body was covered in bony armor plates called osteoderms, which provided protection from predators. Cedarpelta belonged to the Nodosauridae family, a group of ankylosaurs that typically lacked the heavy tail clubs found in their relatives, the Ankylosauridae (like Ankylosaurus itself). Instead, nodosaurids like Cedarpelta likely relied on their dense armor and possibly shoulder spikes for defense.

The skull of Cedarpelta was relatively long and somewhat narrow compared to some other ankylosaurs, and it had a distinctively domed, or convex, shape when viewed from the side. It had a horny beak at the front of its mouth for snipping off plants, and small, leaf-shaped teeth further back, designed for mashing its food. In the classification of dinosaurs, Cedarpelta is placed within Dinosauria, Ornithischia, Thyreophora, Ankylosauria, and specifically within the family Nodosauridae. It is considered one of the earlier, or more “basal,” members of this family, providing clues about the early stages of nodosaurid evolution. It shares some features with other nodosaurids such as Sauropelta, though it also possesses unique characteristics.

Distinguishing Features

Cedarpelta can be identified by several key characteristics:

• A skull that is relatively long for an ankylosaur and noticeably domed on top.
• Some skull bones, like the quadratojugal and squamosal, were not fused together, which is considered a more primitive trait among ankylosaurs.
• Bony armor (osteoderms) that included rows of larger, possibly keeled (ridged) scutes running along its back and sides.
• Like other nodosaurids, it did not possess a bony club at the end of its tail.
• It had a relatively simple structure in its sacrum (the fused vertebrae that connect to the pelvis) compared to later, more advanced ankylosaurs.

Paleoenvironment and Diet

Cedarpelta lived in what is now Utah during the Early Cretaceous. The Cedar Mountain Formation, where its fossils were found, represents an ancient environment that included floodplains, river systems, and possibly semi-arid regions with seasonal rainfall. This ecosystem supported a diverse range of dinosaurs. Cedarpelta would have shared its habitat with large sauropods like Cedarosaurus, plant-eating ornithopods such as Tenontosaurus and Iguanacolossus, and predatory theropods including the fearsome Utahraptor and the unusual therizinosaur Falcarius.

As a herbivore, Cedarpelta’s diet consisted entirely of plants. Being a low browser, it likely fed on ferns, cycads, and other ground-level vegetation that was abundant in its environment. Its beak was well-suited for cropping tough plant material, and its small teeth would have processed the food before it was swallowed. Its wide body and sturdy legs suggest it was a slow-moving animal, spending its days foraging.

Significance and Ongoing Research

Cedarpelta is a significant dinosaur because it is one of the most completely known early nodosaurids from North America. The discovery of its relatively complete skulls has been particularly important, offering valuable insights into the anatomy and evolution of basal nodosaurids. It helps paleontologists understand the diversity of armored dinosaurs during the Early Cretaceous and provides a clearer picture of the animal communities that inhabited the Cedar Mountain Formation.

Ongoing research on Cedarpelta includes further detailed studies of its known fossil material to better understand its anatomy and how it moved. Scientists continue to compare Cedarpelta with other ankylosaur fossils found around the world to refine its place within the nodosaurid family tree and to understand the broader patterns of ankylosaur evolution. Additionally, studies of the sediments in which its fossils were found help to reconstruct its ancient environment and its ecological role within that ecosystem. New discoveries of related dinosaurs may also shed more light on Cedarpelta and its relatives.