Named By: A. Yu. Berezin - 2011.
Classification: Choradata, Reptilia, Sauropterygia, Plesiosauria, Cryptoclididae.
Species: A. nataliae (type).
Known locations: Russia, Chuvashia/Chuvash Republic.
Time period: Hauterivian of the Cretaceous.
Fossil representation: Partial post cranial remains.
Abyssosaurus is a genus of plesiosaur that lived in Russia during the Early Cretaceous. At the time of its description Abyssosaurus was identified as a link between Late Jurassic forms such as Tatenectes and Kimmerosaurus, and Late Cretaceous forms such as Aristonectes and Kaiwhekea. A slightly later study in 2013 by Benson & Druckenmiller identified Abyssosaurus as a close relative of Colymbosaurus.
- A new plesiosaur of the family Aristonectidae from the Early Cretaceous of the center of the Russian Platform. - Paleontological Journal 45(6):648-660. - A. Yu. Berezin - 2011.