An expedition to one of Earth’s most remote corners yielded a remarkable new species, but the discovery comes with an urgent warning
Imagine a forest so high, cold and remote that almost no scientist has ever set foot in it. A place where the clouds themselves seem to settle among the trees, wrapping the canopy in mist.
Now imagine that somewhere in that forest, sitting on the floor of the Amazon basin, a tiny frog — barely an inch long with striking golden irises — has been living for untold generations, unknown to science.
That frog now has a name: Oreobates shunkusacha.
And the story of how it was found, confirmed and described reads like a modern expedition narrative, full of rugged terrain, failed first attempts and the patient, painstaking work of scientific verification.
Where was the new species found?
A team of scientists from Peru and France set out in October 2022 to explore a cloud forest in the San Martín region of Peru.
A cloud forest, for those unfamiliar with the term, is a type of tropical or subtropical forest found at high elevations where persistent low-level cloud cover bathes the environment in moisture. These ecosystems are known to harbor extraordinary biodiversity — but the particular area the researchers targeted had been virtually unexplored.
The reason was simple: the location was too high, too cold and too remote to easily access.
Accompanied by local guides, the team made two trips.
The first attempt ended before they could reach the summit. Difficult terrain forced them to turn back. But persistence is a hallmark of field science, and the second trip proved more fruitful.
The team pushed through to the high-elevation forests — and that’s where they found the frog.
The discovery, though thrilling, was only the beginning.
In field biology, finding an unfamiliar animal does not automatically mean you’ve identified a new species. That determination requires rigorous analysis — comparing physical characteristics, examining genetic material and consulting existing scientific literature to rule out any previously described species.
The team’s work eventually paid off and the frog was confirmed as a unique species in 2024, roughly two years after it was first spotted.
Where did the new frog species get its name?
The species was formally named Oreobates shunkusacha, a tribute to the indigenous people of Peru.
“Shunku Sacha” means “heart of the forest” in the native language of the Kichwa-Lamista people, an expression that speaks to the deep connection between the land and the communities who have long called it home.
Researchers proposed “Shunku Sacha big-headed frog” as the species’ common name.
The formal scientific description of O. shunkusacha was recently published in the German journal Salamandra, a peer-reviewed scientific publication devoted to amphibians and reptiles.
What does the big-headed frog look like?
According to the study, the frog was spotted on the Amazon floor.
It measures just 2-3 centimeters long — small enough to sit comfortably on a thumbnail. Its body is dark brown in coloration, a natural camouflage against the leaf litter and soil of the forest floor.
But what truly distinguishes O. shunkusacha are its striking golden irises, a vivid detail that makes the animal memorable despite its diminutive size.
The frogs live roughly 1,350 meters above sea level — nearly 4,430 feet — placing them squarely in the high-elevation zone of the cloud forest. That elevation is key to understanding the species’ biology and its vulnerability.
“Because these are isolated hills, they act like islands with unique ecosystems in which such species live,” Ernesto Castillo, a herpetologist at Ararankha and the Salamandra study’s lead author, said.
The cloud forest hilltops where O. shunkusacha lives are surrounded by lower-elevation terrain that may be inhospitable to the frog. In ecological terms, this isolation makes the species both unique and extraordinarily vulnerable. After all, there may be no adjacent population to replenish its numbers if its habitat is degraded.
The species is known only from two locations in the department of San Martín: the Sacha Runa Conservation Concession, in the district of Sauce, and the Yaku Kawsanapa Concession, in the district of Chazuta, per Mongabay.
That extraordinarily limited range — a concept biologists call a “restricted distribution” — is one of the factors that makes the frog’s future so precarious.
The new discovery comes with a dire warning
Photo by ERNESTO BENAVIDES/AFP via Getty Images
Even as they announced the discovery, scientists issued a warning: the frog should be classified as endangered due to threats to its habitat.
The numbers are sobering.
Over the past 40 years, the area comprising and surrounding the habitat of O. shunkusacha has lost 60% of its forest cover, according to Mongabay. That’s more than half the forest gone in a single human lifetime.
The main causes of this loss are small-scale coffee and cacao farming, livestock grazing, and illegal logging. These pressures are common across many tropical forest regions.
Conservation efforts in the region center on protecting what scientists and advocates call a “biocorridor” — a connected stretch of habitat that allows species to move, disperse and maintain genetic diversity between otherwise isolated patches of forest.
Without such corridors, isolated populations face heightened risks of decline.
“The greatest challenge is ensuring the protection of the biocorridor,” says Kenneth Mori Ríos, president of the Sacha Runa Ecological Association, per Mongabay.
“It’s a dream we have: to see this entire area free from environmental crimes so that the species being discovered can endure over time. We hope that, with the support of our authorities and partners, we can make this dream a reality,” he added.
His words carry the weight of a community that sees conservation not as an abstract cause but as something deeply personal — a matter of protecting the heart of their forest.
