A team of researchers from the University of Cincinnati (USA) has identified a new species of mosasaur, a fish-eating monster that lived 80 million years ago in the Upper Cretaceous period and is, on average, the best known species. it weighed about 14,000 kilograms.
The scientists named the mosasaur Ectenosaurus everhartorum , after paleontologists Mike and Pamela Everhart. This new species in question inhabited the western Inland Sea in what is now western Kansas and its discovery was announced this week in the Canadian Journal of Earth Sciences.
It is the second species in the genus Ectenosaurus.
“Mosasaurs in western Kansas have been well sampled and well researched. Those two factors create great odds when trying to find something new, ”explains Takuya Konishi, leader of the work and paleontologist in the Department of Biological Sciences at the University of Cincinnati.
Ectenosaurus mosasaurs are unusual for the few specimens that have been found in the genus compared to other mosasaurs.
A marine reptile as big as a small bus
This new species of mosasaurus would have measured more than five meters long and inhabited the Western Interior Seaway, a shallow body of seawater that divided the continent of North America into two distinct land masses. According to experts, this ancient creature of the now extinct genus resembled the false gharial ( Tomistoma schlegelii) , a green-colored crocodilian sauropsid with black spots about four meters long that lives in rivers of Malaysia and West Indonesia.
“If Ectenosaurus clidastoides with its long, slender jaws resembles a gharial crocodile , the new species is closer to a false gharial crocodile with noticeably blunt jaws,” Konishi clarifies.
Mosasaurus inhabited the oceans around the world during the Cretaceous period at the time of Tyrannosaurus re x and this specimen was part of the group of those who were the main ocean predators at that time.
Ectenosaurus everhartorum (a jaw) fossils were first found in 2004 while Konishi was working as a graduate student in systematics and evolution. Konishi was studying fossils of Platecarpus, a different genus of mosasaur stored in the Sternberg Museum of Natural History at Fort Hays State University, when he recognized something strange about a specimen.
“It was not a platecarpus. The frontal bone above the eye socket was much longer. The Platecarpus bones should have had a wider triangle, ”he recalls. “That was a telling sign.”
As a curiosity, the first mosasaur fossils were found in the Netherlands half a century before the term “dinosaur” began to be used. After the Civil War in the USA, when the country’s leading paleontologists, Othniel Charles Marsh and Edward Drinker Cope, began studying the Cretaceous limestone known as Kansas Chalk, this is the time when Kansas emerged as a place worldwide. known for research on mosasaurs.
Referencia: Alexander J. Willman et al. A new species of Ectenosaurus (Mosasauridae: Plioplatecarpinae) from western Kansas, USA, reveals a novel suite of osteological characters for the genus. Canadian Journal of Earth Sciences, published online August 26, 2021; doi: 10.1139/cjes-2020-0175
