Ancient 'hamster' that outlived the dinosaurs found in Siberia

The hamster-sized rodent was a creature of the Jurassic age that seems to have defied extinction until at least the Cretaceous period - 100 to 125 million years ago - before being wiped out. 

Called Baidabatyr (from Baidarka, Russian for kayak, boat, and Batyr - a hero), the animal has been identified from a 2,6 mm long tooth discovered in sediments of the Ilek Formation on the Bolshoy Kemchug River in the south of Krasnoyarsk region.

The site is only 5 kilometres from a mysterious necropolis of baby dinosaurs which is of significant interest to palaeontologists.

Stepan Ivantsov, of the Laboratory of the Mesozoic and Cenozoic Continental Ecosystem, at Tomsk State University, said: 'It is hard to estimate size of the animal based on just one tooth, and even harder to speculate on what it could have looked like. We think it was close to the average size of modern-day rodents, perhaps like a hamster.'

Called  Baidabatyr, the animal has been identified from a 2 mm tooth discovered in sediments of the Ilek Formation on the Bolshoy Kemchug River in the south of Krasnoyarsk region. Pictures: The Journal of Vertebrate Paleontology, Stepan Ivantsov

The mammal is believed to have had poisonous spurs for protection, like the modern-day platypus and echidna, as this was a typical feature of ancient animals. 

Contrary to some reports, Stepan he said: 'Baidabatyr is NOT an ancestor of all currently living plant-eating mammals, but a parallel branch of mammals that doesn't have modern representatives. 

'We know that Baidabatyr lived during dinosaurs time, but we are not sure how many million years it lived. Ilek formation refugium where it was found lasted for forty million years.'

Associate professor Pavel Skuchas, of Saint Petersburg State University, said: 'We discovered a very primitive representative of this group.

'It should have lived in the Jurassic period (more than 145 million years ago), but was found in sediments dating back to the beginning of the Cretaceous period (100 to 125 million years).'

The creature's existence was announced in the Journal of Vertebrate Paleontology. 

Baidabatyr's tooth, pictured below, was 2,6 mm long and 1,3 mm wide. Pictures: The Journal of Vertebrate Paleontology