Ornithischian dinosaur material from the Kuwajima Formation (Tetori Group: Lower Cretaceous) of Ishikawa Prefecture, Japan

Abstract

The Kumajima Formation (Lower Cretaceous: ?Hauterivian–Barremian) of Ishikawa Prefecture, central Honshu, Japan, has yielded a diverse vertebrate fauna that includes a variety of dinosaur taxa. Here, we describe teeth and cranial elements that are referable to an indeterminate styracosternan iguanodontian, an additional unnamed small ornithischian (represented by an isolated maxilla) that is distinct from Albalophosaurus, and other indeterminate ornithischian remains that may belong to the unnamed taxon, Albalophosaurus or another ‘basal’ ornithischian taxon. Iguanodontian specimens are numerically dominant in the available sample of dinosaur material. The Kuwajima Formation has yielded the most diverse dinosaur fauna from Japan and provides a useful point of comparison with other better-known East Asian dinosaur faunas, such as that of the Chinese Jehol Biota.