Spectacular Starry Night Harlequin Toad Rediscovered After Being Lost to Science for 30 Years

A critically endangered toad belonging to one of the most threatened groups of amphibians in the world has been documented by scientists for the first time in 30 years.

The starry night harlequin toad has been lost to science since 1991. However, a collaboration between Colombian non-profit Fundación Atelopus and the Arhuaco indigenous group has managed to capture photographic evidence of the toad in Colombia's Sierra Nevada de Santa Marta—the world's highest coastal mountain range.

The latest evidence is welcome news given that harlequin toads—which are found across Central and South America as far south as Bolivia—have been decimated by deadly fungal pathogens, habitat destruction, habitat degradation, invasive species and climate change.

In fact, eighty of the 96 known harlequin toad species are considered endangered, critically endangered or extinct in the wild, according to the International Union for Conservation of Nature's Red List. Thirty-seven of these species have not been seen since the early 2000s, despite efforts to track them down.

"While harlequin toads across Latin America at these higher altitudes have largely vanished over the past three decades as the result of a deadly fungal pathogen, it turns out that the starry night harlequin toad has bucked the trend," Lina Valencia, Colombia conservation officer at Global Wildlife Conservation—a partner of Fundación Atelopus—said in a statement.

"This is a powerful story about how working with indigenous and local communities can help us not just find species lost to science, but better understand how some species are surviving and how we can conserve the natural world in a way that connects spiritual and cultural knowledge. We are tremendously grateful to the Arhuaco people for giving us this opportunity to work with them," she said.

According to Valencia, the toad is likely poisonous given that all harlequin toads—which features striking black and white markings—have toxins in their skin.

"Its bright coloration gives us clues about their possible toxicity," she told Newsweek. "They live along creeks in mountain forests with low humidity, in one of the driest areas of the Sierra Nevada de Santa Marta."

Even though scientists had not documented the starry night harlequin toad for 30 years, it has always been known to the Sogrome community of the Arhuaco people who live in the Sierra Nevada.

"The Sierra Nevada de Santa Marta is a place that we consider sacred, and harlequin toads are guardians of water and symbols of fertility," Kaneymaku Suarez Chaparro, a member of the Sogrome community, said in a statement.

"We manage our resources and conserve our home as the law of origin dictates, which means that we live in balance with Mother Earth and all of the life here. Now we have a great opportunity to bring together two worldviews for the protection and preservation of the Sierra species: the Western scientific knowledge and the indigenous scientific, cultural and spiritual knowledge," he said.

starry night harlequin toad
A starry night harlequin toad in Colombia's Sierra Nevada de Santa Marta mountain range. Fundación Atelopus

One of the reasons that scientists have not seen the toad for so long is that they have not had access to its habitat. But Fundación Atelopus developed a relationship with the Sogrome community, who agreed to take a team from the non-profit into the field to photograph the species.

"It is an incredible honor to be entrusted with the story of the starry night harlequin toad and the story of the Sogrome community's relationship with it," Fundación Atelopus vice president and biologist José Luis Pérez-González said in the statement.

"We were hoping to find one individual of the starry night harlequin toad, and to our great surprise we found a population of 30 individuals. We were full of joy and hope as we had the chance to observe a healthy population from a genus for which very few species remain," he said.

Conservationists are now working with local indigenous communities to help protect this rare amphibian

"With the starry night harlequin toad records, we confirm that Sierra Nevada de Santa Marta is one of the most important sites for the conservation of harlequin toads in Latin America," Luis Alberto Rueda, professor at Universidad del Magdalena and Fundación Atelopus co-founder, said in a statement. "And thanks to the indigenous communities like Sogrome, this special place continues to be a sanctuary for these special animals."