A previously undescribed specimen reveals new information on the dentition of Sapeornis chaoyangensis

Here we describe the well-preserved skull of a juvenile specimen of Sapeornis, STM 16-18. Only the tail and hindlimb plumage of this specimen have been previously described. It preserves what we consider to be the complete dentition of Sapeornis with four premaxillary teeth, three maxillary teeth and two tiny dentary teeth on each side, the latter feature being previously unknown for this taxon. Based on a study of 71 specimens of Sapeornis...