Oviraptorosaurs ("egg thief lizards") are a group of feathered
maniraptoran dinosaurs from the
Cretaceous Period of what are now
Asia and
North America. They are distinct for their characteristically short, beaked, parrot-like skulls, with or without bony crests atop the head. They ranged in size from
Caudipteryx, which was the size of a turkey, to the 8 metre long, 1.4 ton
Gigantoraptor. The group (along with all
maniraptoran dinosaurs) is close to the ancestry of
birds. Analyses like those of
Maryanska et al (2002) and
Osmólska et al. (2004) suggest that they may represent primitive flightless birds. The most complete oviraptorosaur specimens have been found in Asia. The North American oviraptorosaur record is sparse.