Smallest frog: Paedophryne amanuensis sets world record (Video)
Papua New Guinea -- Researchers have discovered a tiny frog dubbed Paedophryne amanuensis that's just .27 to .31 inches long, small enough that it fits easily on a dime - which sets the new world record for the Smallest frog, according to World Record Academy (www.worldrecordacademy.com).
Photo: The world's smallest vertebrate, discovered by LSU's Austin, is a tiny frog called Paedophryne amanuensis, which averages around 7 millimetre in size and fits in the center of a U.S. dime. Photo Christopher Austin/AFP/courtesy of Christopher Austin at Louisiana State University (LSU) in Baton Rouge (enlarge photo)
The Guinness world record for the Longest amphibian migration was set by the pool frog (Rana lessonae) and the green frog (Rana esculenta) – which have been known to cover distances of up to 15 km (9.32 mi).
Guinness World Records also recognized the world record for the Largest collection of frogs, set by Sheila Crown of Marlborough, Wiltshire, UK who has a collection of 10,502 frog items.
Scientists found the new species, which on average is just 7.7 millimeters long, in the southwestern Pacific island nation of Papua New Guinea.
The researchers came from three different U.S. universities: Louisiana State University, Bishop Museum in Hawaii, and Cornell University in Ithaca, New York.
The frog, scientifically named Paedophryne amauensis, spends its life in moist leaf litter on the floors of tropical wet-forests.
Males call out with a continuous series of high-pitched notes at dawn and dusk, resembling the sound of crickets, says Christopher Austin, associate professor at Louisiana State University who led the team that discovered the frog.
The Paedophryne amauensis is only 7.7 millimetres in length on average and may be the world's smallest vertebrate, researchers said in a PLoS One journal article published Wednesday.
"We think the really small body size is an evolutionary adaptation to occupy this really moist, leaf litter niche in New Guinea," Austin said. Typically, small frogs dry out quickly, but this tiniest species has a habitat that stays moist for most of the year.
Previously the smallest vertebrate was believed to have been a fish known as Paedocypris progenetica, which matures at 7.9 millimeters.
There has been speculation that aquatic habitats are home to the world's smallest and largest vertebrates, but this frog contradicts that theory, Austin says.
Austin, curator of herpetology at LSU's Museum of Natural Science and associate professor of biological sciences, is no stranger to discovering new species, having described numerous species previously unknown to science, including frogs, lizards and parasites.
Austin's work, supported by the National Science Foundation, highlights an interesting trend among the discovery of extremely small vertebrates. "The size limit of vertebrates, or creatures with backbones, is of considerable interest to biologists because little is understood about the functional constraints that come with extreme body size, whether large or small," said Austin.