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''Zapsalis'' is a genus of dromaeosaurine theropod dinosaurs. It is a tooth taxon, often considered dubious because of the fragmentary nature of the fossils, which include teeth but no other remains. The type species is ''Zapsalis abradens'', from the Judith River Formation of Montana, dating to 75 million years ago, during the Campanian stage. Additional teeth attributed to ''Z. abradens'' have been found in the Dinosaur Park Formation, also dated to about 75 Ma ago. While ''Zapsalis''-like teeth have been found in other formations dating to various time periods and assigned to this genus, they most likely belong to new genera and species. In 1876 Edward Drinker Cope named ''Zapsalis abradens'' based on a tooth found in Montana,〔Cope, E.D., 1876, "On some extinct reptiles and Batrachia from the Judith River and Fox Hills Beds of Montana", ''Proceedings of the Academy of Natural Sciences, Philadelphia'', 28: 340-359〕 presently specimen AMNH 3953. The generic name is derived from Greek ''za~'', "thorough", and ''psalis'', "pair of scissors". The specific name means "abrading" in Latin. In 1964 Richard Estes synonymised ''Zapsalis'' with ''Paronychodon'',〔Estes, R., 1964, ''Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming''. University of California Publications in Geological Sciences 49. pp. 180〕 but in 2002 Julia Sankey e.a. concluded the teeth represented a separate "''?Dromaeosaurus'' Morphotype A".〔Sankey J.T., Brinkman D.B., Guenther M., Currie P.J., 2002, "Small theropod and bird teeth from the Late Cretaceous (Upper Campanian) Judith River Group, Alberta", ''Journal of Paleontology'' 76: 751–763〕 In 2013 Derek Larson and Philip Currie recognised ''Zapsalis'' as a valid taxon from the Judith River and Dinosaur Park Formation. The teeth are typified by a combination of rounded denticles, straight rear edge and vertical grooves. Similar teeth from the older Milk River Formation were referred to a ''cf. Zapsalis''.〔 ==See also== * Timeline of dromaeosaurid research 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Zapsalis」の詳細全文を読む スポンサード リンク
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