A “remarkably well-preserved” fossil discovered in Brazil, dating back 113 million years, is now the oldest ant to have ever been found by scientists, a new study has revealed.

The ancient fossil was found preserved in a limestone and “represents the earliest undisputed ant known to science,” the authors write in the study.

The limestone, originating from the Crato Formation, a fossil site in Ceará state in northeastern Brazil, where several prehistoric animals have been unearthed, had been sitting in a collection at the University of São Paulo’s Zoology Museum.

“What makes this discovery particularly interesting is that it belongs to the extinct ‘hell ant’ [subfamily Haidomyrmecinae] known for their bizarre predatory adaptations,” Anderson Lepeco, study lead author and an entomologist at the museum, said in a statement.

“Despite being part of an ancient lineage, this species already displayed highly specialized anatomical features, suggesting unique hunting behaviors,” he added. 

The insect had piercing scythe-like jaws that could probably impale prey from the bottom up. Its jaws also closed vertically like those of humans, rather than horizontally like modern ants.

The hell ant species from Brazil, posthumously named Vulcanidris cratensis, lived during the Cretaceous period 145 million to 66 million years ago, which ended with the extinction event that wiped out most dinosaurs.

The previous oldest ants known to science, hell ants found in France and Myanmar, were estimated to be about 99 million years old. They were all found in amber, or fossilized tree resin.

The discovery from Brazil shows that hell ants were distributed across at least three continents, meaning that ants had a range that extended to all corners of the Earth much earlier than was previously believed. And even though the newly described ant is 14 million years older than the next-oldest hell ant known to science, it holds many of the same complex traits.

“Even these earliest ants had already evolved sophisticated predatory strategies significantly different from their modern counterparts,” Lepeco said. “[It] challenges our assumptions about how quickly these insects developed complex adaptations.”

Banner image: The 113-million-year-old hell ant fossil found in Brazil. Image courtesy of Anderson Lepeco.