THE FIRST RECORD AND DESCRIPTION OF PLIOPLATECARPINI (SQUAMATA, MOSASAURIDAE, PLIOPLATECARPINAE) FROM THE UPPER CRETACEOUS OF SARATOV REGION, RUSSIA

Chudakova Sofya Egorovna

In this article, I describe the remains of a representative of the clade Plioplatecarpini (Squamata, Mosasauridae, Plioplatecarpinae), first discovered in Russia, the frontal bone of the mosasaur Latoplatecarpus willistoni (CSECh 09.2023.1–64) from a location in the quarry area near the village of Karyakino in the Tatishchevsky district of the Saratov region of the Russian Federation (Upper Cretaceous, Campanian tier, Rybushkin formation). From the frontal bones of other representatives of the well-known taxa Plioplatecarpini, the studied specimen differs in pointed posterolateral wings with a straight posterior edge in the transverse direction and a significant depression of the posterior edge from the adjacent posterior process of the parietal bone. Previously, reliable finds of representatives of Latoplatecarpus willistoni were known only from North America (TMP 84.162.01 from the vicinity of Morden, southern Manitoba, Pembina, Canada, Pierre Sheil formation; AMNH 2182 from the vicinity of Mule Creek Junction, Niobrara, eastern Wyoming, USA, Pierre Sheil formation; DMNH 8769 from sediments of the North Sulphur River bank, district Hunt, Northeast Texas, USA, Ozan Formation; SDSMT 30139 from the Red Bird, Niobrara, Wyoming, USA, Pierre Sheil Formation) . The specimen described in this article is of great importance for understanding the paleoecology of Latoplatecarpus willistoni, and significantly expands the understanding of the geographical distribution of Plioplatecarpini.

Keywords:Latoplatecarpus willistoni, Mosasauridae, Russellosaurina, Plioplatecarpinae, Plioplatecarpini, os frontale, mosasaurs of Russia, mosasaurs of the Saratov region, Campanian mosasaurs, Karyakino locality, Rybushkinskaya formation, frontal bone of a mosasaur, skull of a mosasaur