The frogs are characterized by their ability to impersonate a dead leaf, camouflaging the amphibian from predators.
Scientists believe the Northern Darwins have been completely wiped out by a fungal disease called chytridiomycosis that infects the frogs' skin. A similar species also exists in the south, but their numbers too are dwindling.
The northern and southern species are also notable because baby frogs are incubated by their fathers, who keep the eggs warm in their vocal sacs.
Zoologists say that loss of habitat was also probably a contributing factor.
[image via Wikipedia]