Scelidosaurus facts for kids

Quick facts for kids Scelidosaurus Temporal range: Early Jurassic, 196.5–183Ma PreЄ Є O S D C P T J K Pg N
Scelidosaurus cast of the David Sole specimen, in Utah.
Scientific classification

Scelidosaurus was a genus of thyreophorans, a lightly plated, herbivorous dinosaur about 4 metres long. It lived during the Lower Jurassic, 208 to 194 million years ago. Its fossils have been found in both England and in Arizona, in the United States.

Scelidosaurus has been called the earliest complete dinosaur. This and related genera have been found on three continents.

It is one of the earliest and most basal of the armoured dinosaurs. A review by Serano placed Scelidosaurus as the sister group (closest relative) to both the Stegosauria and Ankylosauria.

A full-grown Scelidosaurus was rather small, compared to most other dinosaurs. Some scientists have estimated a length of 4 metres (13 ft). Scelidosaurus was quadrupedal, with the hindlimbs considerably longer than the forelimbs. It may have reared up on its hind legs to browse on foliage from trees, but its forefeet were as large as its hind feet, indicating a mostly quadrupedal posture.

Scelidosaurus and its Jurassic relatives were herbivorous. However, while other ornithischians had teeth capable of grinding plant material, Scelidosaurus had smaller, less complex teeth and a jaw capable of only simple up-and-down jaw movements. In this aspect, they resembled the stegosaurids, which also bore primitive teeth and simple jaws. Also like stegosaurs, they may have swallowed gastroliths to aid processing of food (because of the lack of chewing ability), in the same manner used by modern birds and crocodiles. Their diet would have consisted of leaved plants or fruits, as grasses did not evolve until after Scelidosaurus had become extinct.

Images for kids

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  Skull cast of BRSMG LEGL 0004 with the snout and lower jaw restored

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  Thorax of the neotype.

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  Leg of S. harrisonii

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  Cast of a nearly complete skeleton found in 2000 by David Sole, showing fossilised bony scutes, Charmouth Heritage Coast Centre.

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  Restoration showing bipedal posture, as indicated by a fossil trackway

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  Lithograph of the partial neotype skull.

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  BMNH 39496, the first lectotype of Scelidosaurus, that proved to be a theropod instead.

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  Restoration of the skeleton by O.C. Marsh, showing the long legs at the time presumed for Scelidosaurus

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  Philpot's specimen

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  Skeleton of a young specimen, Bristol City Museum and Art Gallery

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  Dorsal vertebrae.

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  Close up of tooth, and left side of the neotype skull.