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DinoFan83 · 12-24-2020, 09:27 PM

Ceratosaurus (meaning 'horned lizard') was a medium-sized species of ceratosaurid theropod known from the Late Jurassic period of the United States, Portugal, Uruguay, and possibly Switzerland and Tanzania as well. The subadult holotype specimen (USNM 4375) is estimated by Gregory S. Paul to be 5 meters long and 524 kilograms, while the specimen UMNH VP 5278 described as C. dentisulcatus (which may simply be an adult of C. nasicornis and therefore a junior synonym of it) was larger, estimated by Paul at 6 meters long and 700 kilograms. Ceratosaurus was known for its proportionally massive head and deep jaws that supported proportionally very long, blade-like teeth, a prominent, ridge-like horn on the midline of the snout, and a pair of horns over the eyes. These horns were likely to have been used for intraspecific displays among individuals.
The forelimbs were very short, but remained fully functional; the hand had four fingers. The tail was deep from top to bottom, and this along with its long teeth has lead some palaeontologists to speculate that it could have been more efficient at feeding on aquatic life than its contemporaries. A row of small osteoderms (skin bones) was present down the middle of the neck, back, and tail. Additional osteoderms were present at unknown positions on the animal's body.
Within the Morrison Formation where most of its specimens have so far been uncovered, Ceratosaurus fossils are frequently found in association with those of other large theropods, including the megalosauroid Torvosaurus and the allosauroid Allosaurus, but they are sparse in comparison, which may indicate either preservation bias or a much rarer animal on the whole. However, it seems to have been a relatively widespread species across its entire range given that it is known from both North and South America, Europe, and possibly Africa.

DinoFan83 · 12-24-2020, 09:35 PM

Ceratosaurus life restoration by Dmitry Bodganov.