Darwin’s Frog Species Believed ExtinctBy: Mike Fossum - November 20, 2013
A species of frog named after Charles Darwin is thought to have gone extinct, due to a deadly amphibian skin disease. The ironically named Darwin’s Frogs, native to the forest streams of Chile and Argentina, are thought to have succumbed completely to a fungal skin disease called chytridiomycosis.
The frog was first cataloged by by French Zoologist André Marie Constant Duméril and his assistant Gabriel Bibron, and is named after famed naturalist Charles Darwin who, had previously discovered it in Chile during his world voyage on the HMS Beagle. The most defining features of the species are that the tadpoles develop inside the vocal sac of the male, and that the frog itself resembles a leaf, as camouflage from predators.
Researchers believe that it’s the northern variety of the Darwin’s frog that has gone extinct, and that numbers of the southern species have declined dramatically. Andrew Cunningham, from the Zoological Society of London (ZSL), working alongside Chile’s Universidad Andres Bello, states, “Only a few examples of the ‘extinction by infection’ phenomenon exist – Although not entirely conclusive, the possibility of chytridiomycosis being associated with the extinction of the northern Darwin’s frog gains further support with this study.”
The Darwin’s frog (Rhinoderma darwinii and R. rufum) is brown or green, measuring 0.98 to 1.4 inches in length. Though its front feet are not webbed, some of the toes on the back feet typically are. It hunts insects and other arthropods, while likewise evading predators.
Below is an image of the leaf-like body of the Darwin’s frog:
The chytridiomycosis outbreak that killed the frogs is the first report of a widespread presence of Batrachochytrium dendrobatidis in Chile, the fungus that causes the infection. The prevalence of chytridiomycosis in other amphibian species was significantly higher (30%) in areas where either the Darwin’s frogs had become extinct, or were experiencing severe population declines.
Image via YouTube.