Sinemys

Sinemys is an extinct genus of turtle from the Late Jurassic to Early Cretaceous of China. Three species have been named: S. lens, the type species, from the Kimmeridgian-Tithonian of Shandong; S. gamera (シネミス・ガメラ) (named after the movie monster of the same name), from the Valanginian-Albian of Nei Mongol, and S. brevispinus from Early Cretaceous of Nei Mongol. S. wuerhoensis, from the Aptian-Albian of Xinjiang, is not referrable to this genus. Indeterminate specimen that may be belong to this genus is also known from Japan. The species S. gamera is noted for the presence of a pair of elongate spines projecting outwards and backwards from seventh costal of the carapace. These may have served a hydrodynamic function.