Up until now, the smallest vertebrate in the world was a fish of the carp family, Paedocypris progenetica.
They live in dark tea-coloured waters with an acidity of pH3, which is at least 100 times more acidic than rainwater.
P progenetica average a measly 7.9mm in length and are found exclusively in forest swamps on the island of Sumatra.
Now there is a new record holder for the most diminutive vertebrate: Paedophryne amauensis, a minute Anuran (frog) from New Guinea. It was described in a paper in PLoS One by a team of American biologists.
Ecological Guild Evolution and the Discovery of the World’s Smallest Vertebrate. P. amauensis tops the ruler at 7.7mm. It’s not much of a difference, but it does establish a newlimit to miniaturisation.
From Discovery Blogs.
“It was particularly difficult to locate Paedophryne amauensis due to its diminutive size and the males’ high pitched insect-like mating call,” says Louisiana State University scientist Chris Austin, who discovered them.
“But it’s a great find.”
The dark brown frogs with bluish-white specks have likely existed for a long time, underfoot and out of sight on the rainforest floor, eating smaller prey or being eaten by bigger predators.
“The ecosystems these extremely small frogs occupy are very similar, primarily inhabiting leaf litter on the floor of tropical rainforest environments,” says Austin.
“We now believe that these creatures aren’t just biological oddities, but instead represent a previously undocumented ecological guild – they occupy a habitat niche that no other vertebrate does.”
In fact, judging by the frequency of male mating calls they heard, Austin says the tiny frogs might be spaced as close as 50 centimeters from each other on ground beneath the leaves.
And I can never find my glasses.