Polar location of Teete dinosaur fauna (Eastern Siberia, Yakutia)

A few localities world wide are known to have remainsof dinosaurs andothervertebrate animalsthat livedin thepolarlatitude region during the Mesozoic era. The Teete locality in the Vilyui River Basin, Yakutia (Russia) is one of the few known dinosaur localities in the Northern Hemisphere. In 1988, 2002–2012 school children participated in asearch for Early Cretaceous dinosaurs and other vertebrates at the Teete locality, and teeth and bones were collected and briefly described.Additional vertebrate remains, including lizards, salamanders, choristoderes, and tritylodonts, were discovered in Early Cretaceous sediments in Yakutia, which expanded the number of known locations wherethese animals lived in polar regions. In 2017–2019 comprehensive paleontological studies were conducted in Teete,during which time fragmentary skeletal elements and teeth of various dinosaur groups, as wellas bone elements from other vertebrates, were collected using surface collection methods. This study also yielded new genera of Mesozoic mammaliforms,mammals,and salamanders.The presence of astem salamander, basalturtle, and other Jurassic relicts in the Early Cretaceous vertebrate fauna of Teete suggests that the area was a refugium for these animals during that time. Further study of the Teete locality is expected to lead to the description of new dinosaur and other vertebrate taxa, as wellas to theacquisitionof new data on the adaptation of these animals to circumpolar conditions.

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