• 责任者：Hong Dawei (Institute of Vertebrate Palaeontology and Paleoanthropology ; Chinese Academy of Sciences ; Beijing 100044 ; China) ; Xu Xing
• 刊名：Vertebrata Palasiatica
• 出版年：2010
• 卷期：48(1)
• 关键词：晚白垩世 ; Upper Cretaceous ; 兽脚亚目 ; Theropoda ; 河南 ; Henan Province
• 页码：p.19-26
• 图表：2 illus., 1 table, 27 refs.
• 分类号：1103
• issnNo：ISSN1000-3118
• isbnNo：CN11-1905/Q

A single large theropod tooth was recovered from the middle Upper Cretaceous Majiacun Formation, Henan Province, China. The morphology of the tooth strongly suggests that it belongs to a baryonychine spinosaurid theropod. This tooth therefore may represent the first record of the baryonychines in Asia, and the first in the Late Cretaceous. This suggests that the baryonychines were more widely distributed both geographically and temporally than previously thought. Based on the gross morphology and inferred ecology of spinosaurids as a whole, the authors note that these animals are surprisingly rare in the fossil record compared to other theropod clades. This suggests that in life they may have been genuinely rare animals, perhaps as a result of their extreme morphological specialisation.