Fig. 12. Rostral regions (not to scale) of (A) the holotype of Citipati osmolskae IGM 100/978, (B) the holotype of ''Oviraptor'' mongoliensis (IGM 100/32) (reversed), (C) the holotype of Oviraptor philoceratops AMNH 6517, and (D) a referred specimen of the caenagnathid Chirostenotes pergracilis (ROM 43250) (from Sues, 1997). The maxilla of O. philoceratops is relatively longer than in the oviraptorids (B and C) but shorter than in the caenagnathid (D), which represents the plesiomorphic condition for oviraptorosaurians. Arrows indicate premaxilla­maxilla contact anteriorly and palatinemaxilla contact posteriorly. Abbreviations in appendix 1.

Published as part of CLARK, JAMES M., NORELL, MARK A. & ROWE, TIMOTHY, 2002, Cranial Anatomy of Citipati osmolskae (Theropoda, Oviraptorosauria), and a Reinterpretation of the Holotype of Oviraptor philoceratops, pp. 1-24 in American Museum Novitates 3364 on page 19, DOI: 10.1206/0003-0082(2002)364<0001:CAOCOT>2.0.CO;2, http://zenodo.org/record/4734832