Glass frogs may be small, but they have nothing on the Paedophryne amauensis, which at only 0.3 inches in length isn't just the smallest frog, but the world's smallest vertebrate.
It's the size of a housefly and has likely evolved to eat tiny invertebrates, such as mites, that larger predators overlook. This native of Papua New Guinea was discovered in 2009, by researchers who heard its high-pitched call, then scooped leaf litter into a plastic bag to figure out what was making the noise. In addition to its diminutive size, it is unique in that it has no tadpole stage, hatching instead as a miniature of the adult.
Because the frogs have calls that resemble those made by insects and are camouflaged among leaves on the forest floor, Paedophryne amauensis had been difficult to detect. While recording nocturnal frog calls in the forest, Austin and Rittmeyer used triangulation to identify the source of an unknown animal and discovered the frogs by scooping up handfuls of leaf litter and putting it into plastic bags where they spotted the tiny frog hopping around.
