Illustration: two frogs and a pencil
The giant frog Beelzebufo, or "devil frog," may have been the largest frog ever to live on Earth.

Illustration by Luci Betti-Nash, courtesy Stony Brook University

A team of researchers in Madagascar has discovered the fossil of what may be the largest frog to have ever lived. The beach-ball-size amphibian, which grew to be 16 inches (40.6 centimeters) long and weighed about 10 pounds (4.5 kilograms), is scientifically named Beelzebufo, or ‘devil frog.’

Paleontologist David Krause of Stony Brook University in New York made the discovery and is collaborating with other scientists to determine how Beelzebufo is related to other frogs and to understand how and why they are on the island of Madagascar. Fossil frog experts Susan Evans and Marc Jones of the University College London agree that the new frog represents the first known occurrence of a fossil group in Madagascar with living relatives in South America.

"Beelzebufo appears to be a very close relative of a group of South American frogs known as 'ceratophyrines,' or 'pac-man' frogs, because of their immense mouths," said Krause.

But why wasn’t Beelzebufo found in South America? "We're asking ourselves, 'What's a 'South American' frog doing half-way around the world, in Madagascar?'" said Krause. “One possibility is that there was a land connection between South America and Madagascar during [the Late Cretaceous] period." Some researchers believe that Antarctica, Madagascar, and South America may all have been connected at one time.

Beelzebufo is, without a doubt, one of the largest frogs on record and was perhaps the largest frog ever to exist. The size, appearance, and predatory nature of the frog prompted its discoverers to call it the "armored frog from hell." The name “Beelzebufo” comes from the Greek word for devil (Beelzebub) and the Latin word for toad (bufo).

Not only was the frog huge, it was powerful, had a protective shield, an extremely wide mouth and powerful jaws. These features made Beelzebufo capable of killing lizards and other small animals, perhaps even hatchling dinosaurs.

By comparison, the largest living frog today is the goliath frog of West Africa, which can be 12.5 inches (31.7 centimeters) long and weigh about 7.2 pounds (3.2 kilograms). The largest frog alive on Madagascar today is just over four inches (10.1 centimeters) long.