Fanged-Frog Pictures: 9 New Species Found

Protective Parent

Photograph courtesy Jim A. McGuire

An as yet unnamed new fanged-frog species on Sulawesi watches over eggs containing tiny tadpoles.

When Sulawesi fanged frogs first arrived on the island millions of years ago, each species evolved similar adaptations—such as guarding eggs laid on leaves.

"We're seeing repeated incidences of the same adaptation [that] evolved independently," Evans said.

"People think with evolution you could run the 'experiment' again and get a different result." The fanged frogs' evolution seems to suggest otherwise.

(See "Weed Killer Makes Male Frogs Lay Eggs.")

Published August 16, 2011

King of the Jungle

Photograph courtesy Ben Evans

This frog, so far known only as Limnonectes species T, is one of the nine new fanged frogs discovered on Sulawesi.

Unlike on the nearby Philippines, where fanged frogs compete for resources with other frogs, Sulawesi's fanged frogs have no competition. As a result, the Sulawesi amphibians have evolved to fill many evolutionary roles, Evans said.

What's surprising about these frogs is they are so closely related but so morphologically variable"—or physically different, Evans said.

For instance, Sulawesi's fanged frogs all share a common ancestor that lived just 15 million years ago, yet they've rapidly diversified in a "striking" way, he said.

(See new-species pictures: "Fanged Frog, Leopard Gecko, More [2009].")

Published August 16, 2011

Big and Fleshy

Photograph courtesy Ben Evans

Sulawesi fanged frog species (pictured, a new species, tentatively named Limnonectes species I) also vary widely in terms of size.

Some are the size of a human thumb, while others, like Limnonectes species I, are much larger.

(See "Giant 'Frog From Hell' Fossil Found in Madagascar.")

Published August 16, 2011

Harmless Fangs

Photograph courtesy Ben Evans

Another possible explanation for the frogs' fangs (pictured, Limnonectes species T) is that they're for fighting: Males use the spikes in territorial battles over roosting sites or females.

Luckily, the frogs "certainly do not bite you" with their fangs, Evans said—and the protrusions don't have any venom in them.

(See "Frogs Evolve Teeth—Again.")

Published August 16, 2011

Fanged Frog Central

Photograph courtesy Ben Evans

A fast-moving river is a typical habitat for the large fanged frogs on Sulawesi.

The larger frogs tend to have webbed feet and bigger fangs, apparently to assist in moving and hunting in fast water.

The smaller frogs, which spend more time out of water, have toes rather than webbed feet.

"You don't want to walk around with flippers on, if you're on land," Evans said.

(See pictures: "Pea-Size Frog Found—Among World's Smallest.")

Published August 16, 2011