New species is strikingly different from related frogs in Madagascar

By the beam of his headlamp, Carl Hutter immediately knew the frog, not much bigger than a quarter, was a special find. The warty skin and bright red eyes were unlike any he had seen in the high-elevation rainforest of Madagascar.

The country has a great diversity of amphibians, but most recent discoveries are so-called cryptic species, because their appearance closely resembles frogs already known to science. Researchers have been identifying these new species by their genetic differences, using a tool called DNA barcoding, which compares tissue samples to known patterns of genetic markers. The work makes it especially rare for a new frog species to be found in a place that has already been well explored, such as Madagascar’s Andasibe-Mantadia National Park.

But that’s where Hutter, a postdoc at Louisiana State University, Baton Rouge, and his colleagues came across the frog in question in 2015. Reporting last week in Zoosystematics and Evolution, the researchers have named it Gephyromantis marokoroko for its distinctive skin. (The species name means rugged in Malagasy.) The amphibian also has a unique call of two to four pulses followed by a long note—so quiet it can barely be heard even a few meters away. The secretive nature of the nocturnal frog, which seems to only come out of hiding after heavy rains, meant it took several trips over the years to collect enough specimens and recordings for the taxonomic description.

Hutter says G. marokoroko is likely an endangered species, because it has only been found in four patches of forest, some of which are threatened by slash-and-burn agriculture.

doi: 10.1126/science.acy9812