Maybe it’s their compellingly bulging eyes. Maybe it’s because they often look like they’ve been let loose in a paint store filled to the brim with lidless buckets of brightly hued paint. Whatever the reason, amphibians are among the planet’s most charismatic ambassadors for imperiled biodiversity. Faced with a variety of threats, from disease to habitat loss, about half of the world’s roughly 7,000 species of amphibian are threatened with extinction—and more than 250 of those species haven’t been seen since the turn of this century. That’s why Conservation International scientist Dr. Robin Moore launched a six-month, 21-country effort to search for frogs, toads and salamanders that hadn’t been documented in decades. From Borneo to Brazil, Colombia to Congo, and Israel to India, more than a hundred scientists joined this ambitious effort to find some of the most elusive animals on Earth. Here are some of their most spectacular discoveries—animals that have reappeared (or in some cases appeared for the first time) against the odds, proving their resilience and offering hope for future amphibian conservation efforts.

Editor’s Note: This gallery was updated on May 17 to include a photo of the Borneo rainbow toad, a species not seen for 87 years.

Robin Moore

Since venturing into the rainforests of West Africa at age 20 to study chameleons, Robin Moore has been an advocate for animals too often maligned and frequently forgotten. The Search for Lost Frogs, the largest coordinated global search for species lost to science, led to more than 15 rediscoveries and several new species discoveries, and inspired his recent book, In Search of Lost Frogs.

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