Size is all a matter of relativity. An African elephant calf is small in comparison to its adult counterparts—I pray for any woman that has to give birth to a two-hundred pound newborn. But to be the smallest vertebrate walking – or rather hopping – around our planet evokes an entirely different, profound connotation. Take out a dime and place it in either your left or right palm heads up. And now imagine a sexually mature amphibian resting comfortably on Roosevelt’s face. Now that’s small.

Photo © Christopher Austin, Louisiana State University

Photo © Christopher Austin, Louisiana State University

Before its discovery in 2010, a Southeast Asian river fish reined king – or queen – over all things pint-sized. And measuring in at 7.9mm, Paedocypris progenetica truly are tiny things. But the New Guinea native, Paedophryne amanuensis, manages creep up even shorter on the ruler stick—7.7mm to be exact.

Like their stature, information on this groundbreaking species is scant. Paedophryne amanuensis begin life as – and yes, it’s hard to fathom an even smaller animal – miniaturized adults, bypassing the stereotypical metamorphosis. Once mature, the adults then spend the rest of their days prowling the forest floor in hopes of snagging an invertebrate meal. And when the males of the species find themselves “in the mood”, they will emit a high-frequency, insectile call. Interestingly enough, the mating ritual of Paedophryne amanuensis ultimately lead to their discovery. In an effort to identify the acoustical phenomena, The Louisiana State University Professor, Christopher Austin, and his PhD student, Eric Rittmeyer, collected – quite literally – handfuls of forest leaf litter and placed the samples in plastic bags. And it was only then that two saw the tiny amphibians hopping about the clear polyethylene.

Photo © Christopher Austin, Louisiana State University

Photo © Christopher Austin, Louisiana State University

It’s becoming more and more apparent that these incredibly small, niche-filling amphibians aren’t alone. Scientist recently discovered another mini-Kermit, Paedophryne swiftorum – albeit, larger at 8.6mm – in the same collection area as Paedophryne amanuensis. These frogs may be acting as a biotic miticide, helping to maintain balance between plant fauna and mite populations.

Next time you’re out on a nature walk; check the ground ahead of you. You might just be treading over an anuran Whoville.

By Matt Charnock