Chile’s first complete ichthyosaur recovered from a glacier in Patagonia
The fossilised remains of Chile’s first complete ichthyosaur have been unearthed from a melting glacier deep in the Patagonia area of the South American country.
In an expedition led by The University of Magallanes (UMAG) in the Tyndall Glacier area of Chilean Patagonia during March and April 2022, within the boundaries of the Torres del Paine National Park, the intact remains were delicately collected using a helicopter.
Nicknamed “Fiona”, the ichthyosaur is a 4-metre-long pregnant female, containing several embryos that was initially discovered in 2009 by Magellanic palaeontologist and researcher at the GAIA Antarctic Research Centre, UMAG, Dr Judith Pardo-Pérez. Given the remote nature of the find, requiring a 10-hour-hike or horse ride to reach the site, collecting this vitally important specimen was no easy task. It was only made possible through funding provided by the Chilean National Agency for Research and Development (ANID).
The expedition lasted an intense 31 days and was led by Dr Pardo-Pérez, who is the first female palaeontologist to lead a major expedition in Patagonia. The complex logistics, the difficulties of camping and moving around in a rocky area with wildlife including puma, and the extreme weather conditions made this journey an almost titanic challenge.
The exceptional ichthyosaur is the only pregnant female of Valanginian-Hauterivian age (between 129 and 139 million years old from the Early Cretaceous) recorded and extracted on the planet. “At four metres long, complete, and with embryos in gestation, the excavation will help to provide information on its species, on the palaeobiology of embryonic development, and on a disease that affected it during its lifetime,” said Dr Pardo-Perez Pérez, who also reports that, in addition to the ichthyosaur milestone, 23 new specimens have been discovered during this latest campaign, making it, according to Pardo-Perez, the most abundant and best-preserved early Cretaceous ichthyosaur deposit in the world.
“The results of the expedition met all expectations, and even more than expected,” says the scientist, specifying that, from these fossil records, “we hope to obtain results on the diversity, disparity and palaeobiology of the ichthyosaurs of the Tyndall Glacier locality, establish degrees of bone maturity and ecological niches to evaluate possible dietary transitions that occurred throughout their evolution and that could help to establish palaeobiogeographical connections with ichthyosaurs from other latitudes”.
Dr Pardo-Pérez has visited the Tyndall fossil site more than 10 times since the initial discovery in 1997 and completed a PhD on the ichthyosaurs found in the area. Given the magnitude of the proposed research objectives of this trip, the complexities associated with the terrain, as well as the multidisciplinary nature of the study and science, an international team of collaborators with unique skill sets were involved from across Chile, Argentina and also Germany and the UK.
Part of the team was also Dr Dean Lomax, a palaeontologist and a Visiting Scientist at The University of Manchester, who has studied thousands of ichthyosaurs and who recently led the excavation of the Rutland ichthyosaur, the most complete skeleton of a large prehistoric reptile ever found in the UK. Whilst assisting on-site, Lomax found new specimens including the best-preserved skull of an ichthyosaur found there to date, belonging to a young juvenile.
“The fact that these incredible ichthyosaurs are so well preserved in an extreme environment, revealed by a retreating glacier, is unlike anywhere else in the world. The considerable number of ichthyosaurs found in the area, including complete skeletons of adults, juveniles, and newborns provides a unique window into the past. The international collaboration helps to share this exceptional ichthyosaur graveyard with the world and, to a large extent, to promote science.”
Lomax continued: “The weather was so extreme that we could not get to the ichthyosaur site every day and had to remain in camp. On those days when the team could reach the site, they documented the ichthyosaurs and other fossils and discovered new specimens. Amazingly, on average, two ichthyosaurs were found every day.”