World’s smallest frog discovered in Papua New Guinea

It's the size of an Aspirin. Several could fit on a fingernail.

Discovered by American researchers in wet leaf litter on the forest floors of Papua New Guinea, the 7.7-millimetres-long Paedophryne amauensis is the smallest frog on record, and is likely the world's tiniest vertebrate.

"We realized these frogs were probably doing something incredibly different from what normal frogs do—invading this open niche of wet leaf litter that is full of really tiny insects that other frogs and possibly other creatures weren't eating," environmental biologist Christopher Austin said.

This discovery follows the discovery of a slightly larger frog living in the same habitat, the Paedophryne swiftorum.

"This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans [frogs], suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild," the researchers said in a PLoS One journal article.

"Such discoveries are increasingly critical in this time of global amphibian declines and extinctions."

Locating the tiny frogs wasn't an easy task for the group. They tracked the animals by their unusual insect sounds, then scooped up a handful of leaf litter and put it in a bag. The researchers had to go through the bag contents, leaf by leaf, until they found a frog.

Photographing the amphibians was also a challenge as the frogs can leap up to 30 times their body length.