Colin Barras, biomedical and environment news editor
(A) Paedophryne dekot, (B) Paedophryne dekot, (C) Paedophryne verrucosa, (D) Paedophryne verrucosa (Image: Freed Kraus)
These frogs are, by a whisker, the smallest in the world. Adults of the two new species - Paedophryne dekot and Paedophryne verrucosa - are just 8-9 millimetres in length. That makes these diminutive amphibians from Papua New Guinea marginally smaller than 10-millimetre-long frogs found in Cuba and Brazil.
But there's a bigger crown at stake. Frogs are amphibians, but they also belong to a much larger group of animals called tetrapods, which evolved from fish about 380 million years ago. All four-legged animals with a backbone are tetrapods - as are some animals like whales that have lost their legs through evolution. It's likely that these new frogs are the smallest tetrapods living today, says their discover, Fred Kraus from Bishop Museum in Honolulu, Hawaii. That is, until a 7-mm-long frog turns up.
Journal reference: ZooKeys, DOI: 10.3897/zookeys.48.446