Caudipteryx (which means “tail feather”) is a genus of peacock-sized theropod dinosaurs that lived in the Aptian age of the early Cretaceous Period (about 124.6 million years ago). They were feathered and remarkably birdlike in their overall appearance. Two species have been described; C. zoui (the type species), in 1998, and C. dongi, in 2000.
Caudipteryx fossils were first discovered in the Yixian Formation of the Sihetun area of Liaoning Province, northeastern China in 1997.
Caudipteryx, like many other maniraptorans, has an interesting mix of reptile- and bird-like anatomical features.
Caudipteryx had a short, boxy skull with a beak-like snout that retained only a few tapered teeth in the front of the upper jaw. It had a stout trunk, long legs and was probably a swift runner.
Caudipteryx has a short tail stiffened toward the tip, with few vertebrae, like in birds and other oviraptorosaurs. It has a primitive pelvis and shoulder, and primitive skull details in the quadratojugal, squamosal, quadrate, jugal, and mandibular fenestra (in the cheek, jaw, and jaw joint). It has a hand skeleton with a reduced third finger, like that of primitive birds and the oviraptorid Ingenia.
The hands of Caudipteryx supported symmetrical, pennaceous feathers that had vanes and barbs, and that measured between 15–20 centimeters long (6–8 inches). These primary feathers were arranged in a wing-like fan along the second finger, just like primary feathers of birds and other maniraptorans. No fossil of Caudipteryx zoui preserves any secondary feathers attached to the forearms, as found in dromaeosaurids, Archaeopteryx and modern birds. Either these arm feathers are not preserved, or they were not present on Caudipteryx in life. An additional fan of feathers existed on its short tail. The shortness and symmetry of the feathers, and the shortness of the arms relative to the body size, indicate that Caudipteryxwas flightless.
The consensus view, based on several cladistic analyses, is that Caudipteryx is a basal (primitive) member of the Oviraptoridae, and the oviraptorids are nonavian theropod dinosaurs. Incisivosaurus is the only oviraptorid that is more primitive.