Carnosaur

Carnosauria are a subgroup of the theropod dinosaurs. They are the clade Carnosauria. The term was once used very widely, but is now defined more narrowly.

The group includes some of the main carnivores of the Jurassic and Cretaceous periods, such as Spinosaurus, Megalosaurus, Torvosaurus, Allosaurus, Carcharodontosaurus and Neovenator. Modern cladistic analysis defines Carnosauria as those tetanurans which share a more recent common ancestor with Allosaurus than with modern birds.Sereno P.C. 1998. A rationale for phylogenetic definitions, with application to the higher-level taxonomy of Dinosauria. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 210: 41–83

Carnosaurs are characterized by several features. Some features must have been adaptations to their large size, such as their open skull, made of struts rather than solid bone. They had 
large eyes and a long, narrow skull. The femur ("thigh bone") is usually larger than the tibia ("shin bone"). This suggests close-to action was controlled by sight. 

The legs are adapted for running, but not extremely so. They had strong arms, probably used to wrestle prey as the teeth bit in. The structure of an Allosaurus suggests a strongly-built general all-round predator. This is a different from a tyrannosaur like Albertosaurus, which was better adapted for running on open ground. Tyrannosaurs, with their small two-fingered hands, would use their heads for killing prey, and for head-butting rivals.

 Classification 
Infraorder Carnosauria
Altispinax?
Gasosaurus?
Monolophosaurus?
Poekilopleuron?
Megalosauroidea 
Allosauroidea

 References