Nodosauridae is a family of ankylosaurian ornithischian dinosaurs that lasted from the Late Jurassic until the end of the Late Cretaceous. Nodosaurs were quadrupedal, herbivorous animals ranging in sizes between 8 and 23 feet in length. They were similar to ankylosaurids in several ways, including small, leaflike teeth for grinding plants and being covered in osteoderms and spikes, which were used for protection from predators. However, the two families can be distinguished by nodosaurs having a narrower skull, larger spikes (typically situated around the neck and shoulders), and a long tail lacking the bony club common on many ankylosaurs. The family was named when Nodosaurus was named by O. C. Marsh in 1889.
Nodosaurids and ankylosaurids are occasionally found in the same rock formation, and often lived with a ceratopsian and a tyrannosaur or an allosauroid.
Featured species[]
Mymoorapelta[]
Mymoorapelta reconstruction by Jack Wood @thewoodparable
A smaller nodosaur, Mymoorapelta (“Mygatt-Moore shield”) was around 8 to 10 feet in length. It lived during the Jurassic, making it one of the most primitive ankylosaurians found. It is closely related to Gargoyleosaurus, and there has been debate as to whether it belongs to its own family considering its age.
Peloroplites[]
Peloroplites (“monstrous heavy soldier”) is a larger nodosaur, estimated to be around 16 - 20 feet in length and weighing 2.5 tons. It would have fed on low-lying branches and leaves. It was from the Cedar Mountain formation in Utah, living alongside Siats, Eolambia, and Moros.
Antarctopelta[]
At 13 feet in length, Antarctopelta (“Antarctic shield”) was a smaller nodosaur. It is the only known ankylosaur to have lived in what is now Antarctica. Though it was discovered in 1986, it wasn’t officially named until 2006.
Silvisaurus[]
Silvisaurus (“forest lizard”) was a smaller nodosaur from Kansas, making it one of the few dinosaurs found from there. Like its relatives, it had spikes on its neck and tail to protect itself from predators. It had large areas where air would’ve passed through in its skull, possibly helping it make louder sounds.
Hylaeosaurus[]
Reconstruction of Hylaeosaurus
Hylaeosaurus (“forest lizard”) was the third dinosaur to be officially named (1832) as a dinosaur, although the term dinosaur hadn’t been coined yet, only behind Megalosaurus and Iguanodon. Its fossils are fragmented and not a lot more has been found since its discovery. Its bones are still buried in the block of rock it was found in. Some scientists believe it may have been Polacanthus, a polacanthid from Early Cretaceous England.
Sauropelta[]
Sauropelta (“lizard shield”) was a mid-sized nodosaur from Early Cretaceous USA. Found in Texas, Wyoming, Montana, and possibly Utah, it is characterized by the large spikes on its neck, which were used for protection from predators such as Deinonychus and Acrocanthosaurus. It was discovered by Barnum Brown in 1930 but not named and described until 1970 by John Ostrom.
Borealopelta[]
Borealopelta paleoart by Julius Csotonyi
One of the best preserved dinosaurs, Borealopelta (“northern shield”) was covered in osteoderms and had large spikes over its neck and shoulders. These were for defense against theropods like Acrocanthosaurus. The type specimen is so well preserved (a result of quick burial in an environment with rich sediment) its stomach contents have been preserved as well. It may have been a reddish-brown color, as suggested by studies of pigment preserved in skin remnants.
Nodosaurus[]
Nodosaurus (“knobby lizard”) was named after the rows of osteoderms that run along its back and sides. These would have provided defense, as its short legs and large build (20 feet long, 4 - 5 tons) wouldn’t allow it to run from danger. Its teeth were not well suited for feeding on tough plants.
Edmontonia[]
Artist's rendition of Edmontonia
Edmontonia (“from Edmonton”) was a larger nodosaur from Late Cretaceous Alberta, Canada. It is characterized by the large spikes around its neck and shoulders that face forward. These spikes were likely for defense from predators like Gorgosaurus, although because of the forwards angling, it has been suggested rivals pushed against each other in fights for territory. Smaller osteoderms ran along the rest of its body except its underside.