Anomalochelys angulata, an Unusual Land Turtle of Family Nanhsiungchelyidae (Superfamily Trionychoidea; Order Testudines) from the Upper Cretaceous of Hokkaido, North Japan

Ren Hirayama, Kazuhiko Sakurai, Tsutomu Chitoku, Gentaro Kawakami, Norio Kito


Anomalochelys angulata, a new genus and species is described as the most abberant taxon of the Nanhsiungchelyidae (order Testudines, superfamily Trionychoidea), an extinct land turtle group of the Cretaceous, on the basis of a good carapace and partial plastron collected from the Upper Cretaceous of Hobetsu-cho, Central Hokkaido, North Japan. Anomalochelys is unusual in the possesion of the crescent-shaped nuchal with horn-like anterior projections. Its geological age was determined as the Cenomanian by the radiolarian assemblage contained in the matrix.


Anomalochelys; Nanhsiungchelyidae; Testudines; Reptilia; Upper Cretaceous; Japan

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