coelurosaur
Quick Summary
Coelurosaurs were a subdivision of theropod dinosaurs, characterized by their generally small to medium size, though some later members like tyrannosaurs grew much larger. These dinosaurs are defined as birds and all tetanurans more closely related to birds than to carnosaurs.12
Key features of coelurosaurs include:
* A modified pelvis where the ischium is reduced in size compared to the pubis.1
* Larger eyes.1
* No more than 15 tail vertebrae bearing transverse projections.1
The earliest known coelurosaurs, appearing in the Late Jurassic, include species like Compsognathus, which was about the size of a chicken. This group also encompasses a wide range of dinosaurs, from the early, agile predator Coelophysis to the large, formidable tyrannosaurs. Many coelurosaurs are considered ancestors of modern birds.134
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