Northern Dvina River
Dvinia is an extinct genus of cynodonts found in the Salarevo Formation of Sokolki on the Northern Dvina River near Kotlas in Arkhangelsk Oblast, Russia. It is the only known member of the family Dviniidae. Its fossil remains date from the Late Permian and were found with "Inostrancevia", "Scutosaurus" and "Vivaxosaurus".