Paleontologists discover fossilized marine crocodile skull in Vaca Muerta, Argentina

Paleontologists from Argentina have discovered fossil remains of marine animals in the province of Neuquén, in the southwest of the country. Among the significant findings is the skull of a marine crocodile, unearthed in the rocks of the Vaca Muerta formation, which is now renowned for its oil activity. The discoveries were the result of two days of work by specialists from the Cultural Heritage area of Neuquén and the National Council of Scientific and Technical Research (CONICET) in the northern area of the province.

According to a report from the provincial government, these findings corroborate that waters from the Pacific Ocean entered this territory millions of years ago, with indications of a sudden marine ingression about 150 million years ago. Today, the territory is separated from Chile and the sea by the Andes Mountains. The Government of Neuquén reported that these discoveries "corroborate the entry of Pacific Ocean waters into the Neuquén territory millions of years ago."

As part of their work at the site Pampa Tril, the experts found remains of other ichthyosaurs, fish, oysters, ammonites, and the notable skull of a marine crocodile. In 2022, paleontologists had already rescued fossil remains of an ichthyosaur column at this same site. Now, a few meters from that finding, these new discoveries shed further light on the ancient marine ecosystems that once thrived in the area.

Mateo Gutiérrez, one of the experts leading the team of paleontologists, stated, "The skulls can give us anatomical information that allows us to have an overview of the diversity of these animals in the past." He pointed out that "between Chos Malal and Andacollo, rocks of the Los Molles formation were observed, which were deposited in a period of 165 to 180 million years ago and reveal the first marine ingress from the Pacific Ocean in the Neuquén Basin, leaving layers with fossils of marine origin." He highlighted, "This is a finding of relevance, considering that there is not much record of marine reptiles in this geological unit and this would be the first record of ichthyosaurs for this locality."

The same group of researchers achieved the partial rescue of remains of a marine reptile from the group of ichthyosaurs in the Los Molles formation, near the Chacay Melehue stream, also in northern Neuquén. Ichthyosaurs were completely adapted to life in open sea and had an appearance similar to that of current fish or dolphins. In light of the finding of marine fossils, rock samples were taken to conduct micropaleontological analyses that will help determine the age of the remains.

Micaela Chaumeil Rodríguez from the Institute of Research in Paleobiology and Geology (IIPG) stated, "It is not uncommon to find vertebrae and ribs of ichthyosaurs in some marine geological formations of the Neuquén basin, but the presence in this unit and the possibility of finding other elements of the skeleton justifies the rescue of the rest of the animal that is still buried.

The work was logistically supported by personnel from Squadron No. 30 of the National Gendarmerie of Chos Malal, highlighting the importance of inter-institutional collaboration for the protection of heritage. Additionally, the efforts were part of actions carried out by the Ministry of Human Development, Local Governments, and Women for the preservation of Neuquén's natural and cultural heritage.

These significant discoveries not only provide valuable insights into the prehistoric marine life that once inhabited the region but also reinforce the understanding of geological events, such as the ingress of Pacific Ocean waters into Neuquén territory millions of years ago. The findings contribute to the broader paleontological knowledge of marine reptiles and the history of the Neuquén Basin.

Sources: Flora y fauna, Página/12, Clarin

This article was written in collaboration with generative AI company Alchemiq