More Than 10,000-Year-Old Shell From Prehistoric Armadillo Discovered

A group of fishermen discovered an animal shell belonging to a prehistoric armadillo on a riverbank in Argentina, according to reports.

Imanol Ojeda said he spotted the mostly intact shell—which is thought to be more than 10,000 years old—in the sand while he was fishing in Ezeiza, Greater Buenos Aires, Ruptly reported.

The shell is that of a glyptodont—an animal subfamily containing creatures that are the ancestors of modern armadillos. Some of these animals—which went extinct at the end of the last Ice Age around 10,000 years ago—measured up to 11 feet in length and weighed nearly two tons.

The latest discovery comes four years after a similar find in the region. On Christmas Day 2015, Jose Antonio Nievas found a glyptodont shell in mud by a stream in his farm, which is located in Carlos Spegazzini, Greater Buenos Aires, AFP reported.

Initially, Nievas thought that the scaly shell—which measures more than three feet in length—was a dinosaur egg.

"My husband went out to the car and when he came back he said, 'Hey, I just found an egg that looks like it came from a dinosaur," Nievas's wife, Reina Coronel, told AFP. "We all laughed because we thought it was a joke."

Nievas's discovery was featured in a report on local television channel Todo Noticias—which several experts watched. One of these experts subsequently explained that the fossil was not a dinosaur egg but the shell of a glyptodon.

"There is no doubt that it looks like a glyptodont," paleontologist Alejandro Kramarz, from the Bernardino Rivadavia Natural Sciences Museum in Argentina, told AFP.

Glyptodons emerged in South America no earlier than 35 million years ago, according to a 2016 study published in the journal Current Biology

Featuring large, round, armored shells made up of bony plates, glyptodonts are the ancestors of modern armadillos. These animals also had armored tails which could act as a lethal club. In fact, the tails of some glyptodont species featured a knob of bone on the end that was spiked.

The animals were not fussy eaters, consuming almost anything they could find—including plants, carrion and insects, according to the Encyclopaedia Britannica.

"The animal became extinct thousands of years ago and it is very common to find their fossils in this region," Kramarz told AFP.

According to Kramarz, the specimen found by Nievas likely lived just over 10,000 years ago.

In the 2016 Current Biology study, scientists confirmed the ancestral links between glyptodonts and modern armadillos.

They found that glyptodonts represent a distinct subfamily (Glyptodontinae) within the family known as Chlamyphoridae—which today includes animals such as the dwarf pink fairy armadillo and the giant armadillo.

Researchers think that for most of their history, glyptodonts were very successful and the reasons for their disappearance are still up for debate.

"Almost all mega-mammals of South America became extinct about 10,000 years ago at the end of the last Ice Age, but their cousins, the armadillos, survived, Laura Edith Cruz, from the Bernardino Rivadavia Natural Sciences Museum, told Newsweek.

The shell and a replica of a glyptodont found near Padilla, southeastern Bolivia, on September 19, 2014. AIZAR RALDES/AFP/Getty Images