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Neoceratosauria

The earliest known neoceratosaurids are from the Late Jurassic of western North America and eastern Africa, though most are known from Upper Cretaceous sediments. They were medium- to large-sized carnivores (up to about 30 feet long) with large, deep skulls. Some had tiny forearms, much like tyrannosaurids. Many neoceratosaurids had some kind of skull ornamentation, like the nasal horn and small horns over the eyes in Ceratosaurus.

Neoceratosauria is made up of the Abelisauridae, Ceratosaurus from the Late Jurassic Morrison Formation of Utah and Colorado, and a handful of species whose place within Neoceratosauria is still the subject of debate.

The external surface of abelisaurid bones have extensive pitting and sculpturing, a feature not seen in the other neoceratosaurs. Abelisaurids include Majungatholus, from the Late Cretaceous of Madagascar, and Abelisaurus and Carnotaurus, both from the Late Cretaceous of Argentina.

One of the problematic neoceratosaurids that seem to be closely related to abelisaurids is Noasaurus from the Late Cretaceous of Argentina. Another is Masiakasaurus from the Late Cretaceous of Madagascar — it differs from other neoceratosaurians in that its front teeth project forward. Elaphrosaurus, from the Late Jurassic of Tanzania, awaits the discovery of a skull — at present, it is only known from postcranial material and a skull would help considerably in resolving its place within the Neoceratosauria.

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Original page created by David Smith 5/2008.