Metasuchian

Metasuchian is a term used in paleontology to describe a group of theropod dinosaurs that includes both the coelurosaurs and the tyrannosauroids. The term was coined by paleontologist Paul Sereno in 1998 to reflect the close evolutionary relationship between these two groups. Metasuchians are characterized by several unique features, including a long, low skull, a long neck, and a long tail. They are also known for their diverse range of adaptations, including those for hunting, scavenging, and herbivory.

The earliest known metasuchians date back to the Late Triassic period, around 230 million years ago. They became one of the most successful groups of dinosaurs during the Mesozoic era, with numerous species evolving and adapting to a wide range of environments. Some of the most well-known metasuchians include the velociraptors, tyrannosaurs, and troodontids.

Metasuchians are further divided into two main subgroups: the coelurosaurs and the tyrannosauroids. Coelurosaurs are characterized by their lightweight, agile bodies and include species like velociraptor and dromaeosaurids. Tyrannosauroids, on the other hand, are known for their large size and powerful jaws, with species like tyrannosaurus rex and gorgosaurus being prominent examples.

The study of metasuchians continues to be an active area of research in paleontology, with new species and fossils being discovered regularly. These dinosaurs provide valuable insights into the evolution of theropod dinosaurs and the diversity of life during the Mesozoic era.