November 17 – .
Researchers on Thursday described the remains of a species of sea turtle called Leviathanochelys aenigmatica that was about 3.7 meters long and weighed less than two tons and lived during the Cretaceous period — the final chapter of the age of dinosaurs — found in northeastern Spain. It is the largest known sea turtle in Europe.
It dwarfs today’s largest sea turtle
The leatherback, which can grow up to 2 meters long and is known for its marathon ocean migrations. Leviathanochelys is nearly equal to the largest ever tortoise – Archelon, which lived about 70 million years ago and grew to about 4.6 meters long.
« Leviathanochelys was as long as a Mini Cooper
And Archelon was as big as a Toyota Corolla, » said study co-author Albert Sellés, a paleontologist from the Institut Català de Paleontologia (ICP) in Catalonia. Autonomous University of Barcelona..
It’s a good thing the car is that big
Considering the treacherous traffic in the ancient Tethys Sea where the Leviathan dragon swam. Huge marine reptiles with powerful jaws, called mosasaurs, were some of the largest predators – some reaching over 15 meters in length. A variety of sharks and rays lurk, as well as long-necked fish-eating marine reptiles known as plesiosaurs.
« Attacking an animal the size of Leviathanochelys could only have been carried out by large predators in the marine environment. At the time, large marine predators in the European region were mainly sharks and mosasaurs, » said paleontology graduate student Oscar Castillo. from the Autonomous University of Barcelona, lead author of the study published in the journal Scientific Reports.
« During the Cretaceous period
Sea turtles tended to increase in size. Leviathanochelys and Archelon may represent the culmination of this process. The height increase is thought to be due to predatory pressure, but there may be other factors, » Castillo added road.
Other large tortoises from Earth’s past include Protostega and Stupendemys
Both of which grew to about 4 meters in length. Protostega, a Cretaceous sea turtle that lived about 85 million years ago, like its eventual cousin the Archelon, inhabited the large inland sea that then divided North America in two. During the Miocene period, about 7-13 million years ago, Stupendemys roamed the lakes and rivers of northern South America.
Scientists discovered the remains of Leviathanochelys near the village of Coll de Nargó in Catalonia’s Alt Urgell county, after a hiker found fossils sticking out of the ground in the southern Pyrenees. So far, they’ve recovered the carapace, or part of the back of the carapace, and most of the pelvic girdle, but no skull, tail or limbs.
Les fossiles montrent qu’elle avait une carapace lisse semblable à celle d’une tortue luth
Et la carapace elle-même mesurait environ 7,7 pieds (2,35 mètres) de long et 7,2 pieds (2,2 mètres) de large. Les léviathanochelys semblent être construits pour l’océan ouvert et retournent rarement sur terre – par exemple pour frayer.
Plusieurs saillies osseuses sur la face avant du bassin ne ressemblent à aucune autre tortue de mer connue, ce qui suggère que les Léviathanochelys représentent une lignée nouvellement découverte. Il montre que le gigantisme chez les tortues marines s’est développé indépendamment dans différentes lignées du Crétacé en Amérique du Nord et en Europe.
Leviathanochelys aenigmatica signifie « tortue mystérieuse » en raison de sa grande taille et de sa forme étrange, ce qui, selon les chercheurs, a quelque chose à voir avec son système respiratoire.
« Certains animaux pélagiques (vivant en haute mer) ont modifié leur système respiratoire pour maximiser leur capacité à respirer dans l’océan profond », a déclaré Sellés.
💡 Ressources et références
« Reuters.com », via : Un fossile de tortue de mer de l’ère des dinosaures de la taille d’une voiture découvert en Espagne.