Dacentrurus armatus
Dacentrurus armatus was one of the largest stegosaurs known and lived in what is now western Europe during the Late Jurassic. It walked on all fours, with powerful hind limbs, much shorter forelimbs and a small head carried close to the ground.
Dacentrurus
Dacentrurus armatus
AI-rekonstruktion · Dinofakta / Google Gemini (AI-genererad rekonstruktion © Dinofakta)
Explore together
Plenty to talk about here: how long ago it was, how a fossil forms, and how we can know so much about animals that died out millions of years ago.
Quick facts
Perfect for kids and families
Weight
3000–5000 kg
Length
7–9 m
Diet
Herbivore
Period
Jurassic
Mini challenge
Try together before you keep scrolling
Pick an answer
3000–5000 kg
7–9 m
Jurassic
Quadrupedal
1.7–2.5 m
7 km/h
Herbivore
13 recorded fossil finds in Spain, Portugal, and United Kingdom. Most in Centro, Valencia, and Aragón. First described in 1877 by Marsh.
Sites and counts from the Paleobiology Database
The timeline shows the whole age of dinosaurs – and how much time has passed since. The glowing part is when Dacentrurus lived.
million years ago
Lived 157–145 million years ago
If the whole age of dinosaurs were a single day, Dacentrurus lived at 13:02.
Chapter • Meet the dinosaur
Dacentrurus armatus was one of the largest stegosaurs known and lived in what is now western Europe during the Late Jurassic. It walked on all fours, with powerful hind limbs, much shorter forelimbs and a small head carried close to the ground. Rows of small, narrow plates or spine-like osteoderms ran along the neck and back, while the hips and tail carried long, pointed spikes. The tail ended in four large spikes – the thagomizer – which served as a defensive weapon. The hip region was strikingly broad, and the thigh bones are among the most robust known from any stegosaur. Like all thyreophorans, Dacentrurus had no feathers; its body was covered in scaly skin studded with bony plates and small ossicles.
Chapter • Where it lived
Dacentrurus lived roughly 157–145 million years ago, during the Kimmeridgian and Tithonian stages of the Late Jurassic. Europe was then an archipelago of islands and low coastal plains under a warm, subtropical climate. The animal moved across floodplains and through open conifer and fern woodlands near the sea. The holotype comes from the Kimmeridge Clay near Swindon in Wiltshire, England, and abundant material has been recovered from the Lourinhã Formation along the Portuguese coast, as well as from Spain and France.
Chapter • Wild behavior
Diurnal
No bonebeds containing several individuals of Dacentrurus are known, so we genuinely do not know whether it lived alone or in groups. The long spikes over the hips and tail may have served both for defence against predators such as Allosaurus or Torvosaurus and for display towards members of its own species, but both readings are hypotheses. Its social life is best described as unknown.
The name Dacentrurus means roughly 'tail with sharp points', a reference to the tail spikes.
The species was described as early as 1875 by Richard Owen, but under the name Omosaurus armatus.
Because Omosaurus was already used for a crocodile, Frederick Lucas renamed the genus in 1902.
That makes Dacentrurus one of the earliest stegosaurs ever named – older as a name than Stegosaurus itself.
At up to about nine metres long it ranks among the biggest stegosaurs that ever lived.
Fossils are known from England, Portugal, Spain and France, making it a classic European dinosaur.
Some researchers argue that the long-necked Portuguese stegosaur Miragaia is actually the same animal as Dacentrurus, but the question remains debated.
Its brain was very small relative to its body, yet the skull bones suggest a well-developed sense of smell.
Chapter • Scientific place
PLOS ONE
Reviewed: 9/6/2026
Peer-reviewed phylogenetic analysis placing Dacentrurus armatus within Dacentrurinae inside Stegosauridae (Stegosauria, Eurypoda, Thyreophora, Ornithischia).
Open sourcePaleobiology Database
Reviewed: 9/6/2026
Database taxon page compiling the recorded fossil occurrences, collections and stratigraphic/geographic distribution of Dacentrurus armatus across Late Jurassic Europe.
Open sourceActa Palaeontologica Polonica
Reviewed: 9/6/2026
Peer-reviewed study of stegosaur trackways documenting the coastal-plain and floodplain palaeoenvironment of the Lourinhã Formation in which Dacentrurus lived.
Open sourcePaleobiology Database
Reviewed: 9/6/2026
Taxon record listing the ecology of Dacentrurus armatus as a ground-dwelling herbivore, consistent with stegosaurid low-browsing plant feeding.
Open sourceComptes Rendus Palevol (Elsevier)
Reviewed: 9/6/2026
Extinct taxon; conservation status NE
Open sourceZoological Journal of the Linnean Society (Oxford University Press)
Reviewed: 9/6/2026
Peer-reviewed osteological description and taxonomic overview of Dacentrurus armatus, serving as the general authoritative reference for the species description text.
Open sourceZoological Journal of the Linnean Society (Oxford University Press)
Reviewed: 9/6/2026
Peer-reviewed osteological description and taxonomic overview of Dacentrurus armatus, serving as the general authoritative reference for the species description text.
Open sourceZoological Journal of the Linnean Society (Oxford University Press)
Reviewed: 9/6/2026
Peer-reviewed osteological description and taxonomic overview of Dacentrurus armatus, serving as the general authoritative reference for the species description text.
Open sourceZoological Journal of the Linnean Society (Oxford University Press)
Reviewed: 9/6/2026
Peer-reviewed osteological description and taxonomic overview of Dacentrurus armatus, serving as the general authoritative reference for the species description text.
Open source