The remains were discovered in July in Peru’s Ocucaje Desert, an area south of the capital Lima that was once part of the Pacific Ocean.

Paleontologist Mario Urbina, who was part of the discovery, referred to the ancient site as a “great hotel,” explaining that coastal mountains created a barrier from strong currents, making it an ideal, calm place for marine animals to reproduce.

The region was a sea for approximately 45 million years.

Researchers from Peru’s state Geological, Mining and Metallurgical Institute (INGEMET) noted that the discovery helps them understand the geography of the past and how the coastline has changed over millennia.

Peru’s deserts are considered a rich cemetery for ancient marine species, with a 9-million-year-old fossil of a great white shark relative found earlier this year.

Prehistoric remains have also been found elsewhere in Peru in regions away from the coast. In April 2024, experts presented the fossilised skull of the largest known river dolphin, which inhabited what is now the Amazon about 16 million years ago.