Sauropelta edwardsorum SOR-oh-PEL-tah

"Lizard shield"

Sauropelta silhouette
You 1.8 m (5.9 ft) tall
Sauropelta 5.2 m (17.1 ft) long
3 people holding hands
silhouette · Marie Aimée ALLARD (CC0) via PhyloPic
Length
5.2 m (17.1 ft) — About 5.2 m long, ~1.5 tonnes — armored but no tail club.
Period
Early Cretaceous (115–108 Mya)
Place
North America · Wyoming · Montana
Food
Herbivore — Low-growing plants, probably ferns and tough cycad fronds.
Clade
Nodosauridae Dinosauria Ornithischia Thyreophora Ankylosauria

Sauropelta was a nodosaurid — an ankylosaur cousin that traded the heavy tail club for long shoulder spikes. The shoulders carried two pairs of sideways-pointing spikes that probably warded off attackers from the side. Unlike Ankylosaurus, the tail was flexible and unarmored at the tip.

What we know

  • Long sideways-pointing shoulder spikes — the longest of any nodosaur.
  • Skin armor across the back, but no tail club.
  • Lived alongside Deinonychus in the Cloverly Formation.
  • Wide barrel-shaped body for plant fermentation.

What we guess

  • Whether the shoulder spikes were primarily defensive or also for display.
  • How it survived attacks by Deinonychus — possibly by crouching to expose only its armored back.
  • Whether nodosaurids and ankylosaurids descended from a common armored ancestor or evolved armor separately.