A Ceratopsian Dinosaur From Hauterivian/Berremian Cretaceous Japan

The First Basal Neoceratopsian Dinosaur from the Lower Cretaceous Kanmon Group in Kyushu, Southwestern Japan

Authors:

Tanoue et al

Abstract:

An isolated tooth specimen from the Lower Cretaceous Kanmon Group in Kyushu Island, south-western Japan was initially identified as a hadrosaurid. It is reidentified herein as a neoceratopsian tooth based on the presence of a wide and prominent primary ridge on the crown, a shallow indentation on the right side of the primary ridge in non-occlusal view, and a horizontally oriented cingulum at the base of the crown. The poorly developed cingulum and shallow indentation suggest that it does not pertain to a ceratopsid, but is only referable to a basal neoceratopsian. This represents the first basal neoceratopsian specimen from the Lower Cretaceous of Kyushu Island.