A new genus and species of elasmosaurid, a type of plesiosaur with a very long and slender neck, has been identified from fossilized remains found near the site. marambio basea permanent year-round Argentine Antarctic base on Marambio Island.
rebuilding the life of Marambionectes molinai. Image credit: O'Gorman other., doi: 10.1080/14772019.2024.2312302.
Elasmosaurs are members of Elasmosauridaea family of plesiosaurs that flourished during the Cretaceous period, approximately 145 million to 66 million years ago.
These creatures were perfectly adapted to aquatic life and had a unique body shape consisting of a streamlined body, paddle-like limbs, and an extremely long neck with up to 75 vertebrae.
The new species is Marambionectes molinai lived in the Cretaceous seas about 67 million years ago.
The fossil was recovered from the upper layer. López de Bertodano's formation February 2018, James Ross Islands, Antarctic Peninsula.
“The collected remains were Marambionectes molinai This includes parts of the torso and tail, limbs, neck and skull, as well as gastroliths called gastroliths, which were probably used for the mechanical digestion of food,'' CONICET paleontologists said. said. Jose O'Gorman and his colleagues.
“They were rescued in the first operation, but it was an intense and tiring experience punctuated by several days of snowstorms. The research team was isolated in a shelter, waiting for better weather to complete the work. Ta.”
material of Marambionectes molinai. Image credit: O'Gorman other., doi: 10.1080/14772019.2024.2312302.
Phylogenetic analysis is restored Marambionectes molinai within a clade Weddelonexia As a sister group of sub-families Arisnectinae.
In this sense, the authors suggest that some of the skeletal features of Alysnectinians may have been acquired through a process that began in the non-Alysnectinian elasmosaurids, prior to the emergence of this clade. are doing.
“Although not perfect, the overall state of preservation of the specimen is exceptional, even for skull material,” the paleontologists said.
“We confirm that it is not only a new species, but also has special characteristics that allow us to identify it as a form of transition between two groups that lived in the southern hemisphere. It has shed light on the evolutionary processes and relationships between the genera and other genera found in Chile, New Zealand, and West Antarctica. ”
discovery of Marambionectes molinai is reported in paper inside Journal of Systematic Paleontology.
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Jose P. O'Gorman other. 2024. New elasmosaurids (plesiosaurs: Sauropterygia) from the López de Bertodano Formation: new data on the evolution of alisnectin morphology. Journal of Systematic Paleontology 22(1); doi: 10.1080/14772019.2024.2312302
Source: www.sci.news
