Eocarcharia

Eocarcharia (meaning "dawn shark") is an extinct genus of theropod dinosaurs found in what is now the western Ténéré Desert of Niger. It is known from several skull bones collected in 2000 by an expedition to the Early Cretaceous (Aptian–Albian ages) Elrhaz Formation (Gadoufaoua locality) led by American paleontologist Paul Sereno. They were then described in 2008 by Sereno and Steve Brusatte. The genus contains a single species, Eocarcharia dinops. Sereno and Brusatte identified the remains as a new carcharodontosaurid, but later studies suggested that the species is chimaeric, comprising bones of at least two unrelated taxa. Some of the Eocarcharia material, including the holotype (name-bearing) specimen, likely belongs to a baryonychine spinosaurid. This would render Eocarcharia a member of this group, closely related to the coeval Suchomimus. Meanwhile, the definitively carcharodontosaurid bones, a maxilla and teeth, belong to a separate distinct taxon.

Little is known about Eocarcharia due to its fragmentary and chimaeric nature. When considered a carcharodontosaurid, it was estimated to be 6–8 metres (20–26 ft) long, making it smaller than derived carcharodontosaurids like Giganotosaurus, and Carcharodontosaurus. The postorbital (bone behind the orbit) is robust with a large brow, a distinct characteristic of Eocarcharia. It was possibly covered in keratin and used for head-butting with other individuals of its species. Eocarcharia lived in an environment with rivers and vast floodplains alongside many other dinosaurs, pterosaurs, crocodylomorphs, and freshwater animals.