Polacanthus

Filed under Cretaceous dinosaurs · Types of Dinosaurs editorial team

Order: Ornithischia · Suborder: Thyreophora · Infraorder: Ankylosauria · Family: Polacanthidae (family not firmly confirmed)

Polacanthus was an armoured dinosaur that lived during the Early Cretaceous period in what is now England, and it stands as one of the earliest such dinosaurs to have been formally described by science. Belonging to the family Polacanthidae, it reached a length of roughly 16 to 18 feet, making it a substantial animal for its time and place. Its name, meaning "many spines," reflects the most immediately striking feature of its anatomy: a dense array of spines and spikes that projected from its shoulders and ran along its back, supplemented by a fused shield of bony armour covering the hip region.

Unlike some later armoured dinosaurs, Polacanthus lacked a tail club, meaning its primary defence against predators relied entirely on this formidable covering of spikes and plates. As a low-browsing herbivore, it would have fed on vegetation close to the ground, sharing its environment with well-known contemporaries such as Iguanodon. Polacanthus remains a significant example of early armoured dinosaurs from Europe, offering paleontologists a valuable window into the diversity of ankylosaur relatives that populated the region during the Early Cretaceous.

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Reference background: Natural History Museum, London — Dinosaurs; Smithsonian National Museum of Natural History — Dinosaurs; American Museum of Natural History — Dinosaurs & Fossils. Figures are typical published ranges; taxonomy follows the source era and modern consensus is noted where it differs. See our sources & fact-check policy.

Related dinosaurs

Other dinosaurs from the Polacanthidae family.