The Polycotylidae, an interesting group of marine reptiles, are first known to have appeared in the Aptian period in Australia. However, their evolutionary journey was not limited to the continent, because this group managed to cross the ocean and reach North America in the Albian period. Interestingly, the Polycotylids not only spread across North America, but also managed to achieve a cosmopolitan distribution, spreading to various regions of the world before finally becoming extinct along with the rest of the Plesiosaurs at the end of the Maastrichtian period.
The journey and widespread distribution of polycotylids is a remarkable evolutionary story, reflecting the group’s adaptability and ability to move across oceans. Their ability to reach North America and spread globally provides insight into ancient marine connectivity, as well as their important role in marine ecosystems of that time.
“Polycotylids had plesiosaur bauplans with broad, hydrodynamic bodies with short tails, four limbs modified into large paddles, and widened pectoral and pelvic girdles, but they also had the derived condition of short necks and large heads with elongated rostrums,” said lead author Robert Clark.
Although they eventually became extinct along with the rest of the Plesiosaurs at the end of the Maastrichtian, knowledge of the long journey and cosmopolitan distribution of polycotylids provides a solid foundation for researchers to understand their role and evolutionary impact in the history of marine life.
2024-01-23 19:10:12
#Identification #Species #Plesiosaur #United #States
