Irritator (say: irr-irr-it-at-or) is a genus of spinosaurid theropod dinosaur that lived in what is now Brazil during the Lower Cretaceous. Its fossils are known from the Romualdo Formation. Irritator had straight and cone-shaped teeth. Its jaws were low, long and slender, with the nostrils placed well back from the front of the snout (all consistent with fish eating). Irritator also had a narrow crest made of nasal bones on top of the skull. Irritator's name comes from the English word "Irritation". It was given its name due to the feelings of the scientists who described it when they found that fossil dealers had added plaster to the front of the snout.
|Reconstructed skeleton at the National Museum of Nature and Science, Tokyo. The postcranium is based on remains that cannot be confidently attributed to the animal.|
Martill et al. 1996
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