Nodosaurids share the low-slung, heavily armored body plan of their better-known relatives the ankylosaurids, with rows of bony osteoderms embedded in the skin across the back and flanks, often extending into prominent shoulder or flank spikes. What they lack is the ankylosaurid tail club -- nodosaurid tails stayed flexible and unweaponized, meaning their primary defense was passive: presenting an armored, low profile that large predators had trouble flipping or biting into.
The family ranged from the Jurassic into the Cretaceous, with genera like Edmontonia and Sauropelta well known from North America. The most striking nodosaurid find in recent years is Borealopelta, a Canadian specimen so exceptionally preserved that scientists were able to reconstruct its original coloration -- a reddish-brown countershading pattern, evidence that even a heavily armored animal still needed camouflage against predators.