Over the course of the next five years, the team found several more bone fragments of Beelzebufo ampinga. In the new study, they combined all of the fragments to do a much more complete reconstruction of the devil frog.
The new analysis confirms the frog's lineage in the Ceratophryidae family. It also downgrades the amphibian's size -- instead of being the biggest frog that ever lived, it may be closer to the size of an African bullfrog, which grows to about 10 inches (25.4 centimeters) across.
Even so, the analysis reveals that the devil frog was even fiercer-looking than previously thought. Past studies had suggested it had a huge, globular head; sharp teeth; and short back legs, but the spiky flanges and the plates embedded in its skin were a surprising discovery.
The frogs may have hunted like African bullfrogs, hiding before pouncing on a small mammal.
It's not clear what the frogs used the body armor for, but one possibility is that the sculptured bones may have been an adaptation to a dry environment that allowed the frogs to burrow underground, where they were less likely to bake in the hot sun, Evans said.
But the armor may also have been protection.
"There were an awful lot of things roaming around that would have liked a bite out of a big, juicy frog," such as dinosaurs, crocodiles and even strange mammals that once lived on the Gondwana supercontinent, Evans told LiveScience.
The findings were published Jan. 28 in the journal PLOS ONE.
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