Triassic 'tank' unearthed in Texas was a croc cousin that lived 215 million years ago

A huge armored crocodile cousin with plates embedded in its skin and curved spikes along its flanks roamed our planet 215 million years ago, scientists reveal.

The newfound species, discovered in the Cooper Canyon Formation in northwestern Texas, was an aetosaur. These stout-limbed beasts grew up to 16 feet (5 meters) long and were covered in bony plates called osteoderms for protection. They were "tanks of the Triassic," according to a statement released by The University of Texas at Austin.

Researchers unearthed a large portion of the creature's dorsal carapace, or back armor, the researchers said in a study, published Jan. 11 in the journal The Anatomical Record.

"We have elements from the back of the neck and shoulder region all the way to the tip of the tail," lead author William Reyes, a doctoral student at The University of Texas at Austin, said in the statement. "Usually, you find very limited material."

Aetosaurs ruled Earth during the late Triassic (237 million to 201 million years ago), living on every continent except Australia and Antarctica, according to the statement. Unlike modern crocodiles, which are strictly carnivores, aetosaurs were primarily omnivores.

Related: Stunning 240 million-year-old 'Chinese dragon' fossil unveiled by scientists

The late paleontologist Bill Mueller discovered the newly described fossil with local amateur collector Emmett Shedd in 1989. Preliminary research in the early 2000s found that the animal was likely a new species of aetosaur, but didn't decipher its evolutionary History.