Brachycephalus auroguttatus (Photo: PeerJ, Ribeiro, et al., CC BY 4.0)

Tiny and bright Brachycephalus frogs live on the tops of Amazon mountains: they have very particular needs—so particular that they never make it down into the valleys.

Ecologically, these mountaintops are like “sky islands,” where isolated populations evolve over time into new species. But as a team of Brazilian scientists writes “the difficulty of exploring these inaccessible habitats…severely limits the chance of discovery of new species” of frog. Which is why the team went looking for them.

 Brachycephalus leopardus, mating (Photo: PeerJ, Ribeiro, et al., CC BY 4.0)

In a new paper, published in PeerJ, the team reveals that through “extensive fieldwork” they were able to discover seven new species of Brachycephalus frogs—increasing by a third the known number of Brachycephalus species. These frogs are distinguished from each other by their bright colors and the roughness of their skin. And there are probably still more out there: “More than half of the currently recognized species have been described during the past 15 years, suggesting the possibility that the actual diversity in the genus is considerably underestimated,” the team writes.

Brachycephalus leopardus, not mating  (Photo: PeerJ, Ribeiro, et al., CC BY 4.0)

Finding these was hard enough, though. Marcio Pie, one of the paper’s authors, told the BBC that “he had climbed more mountains than he can remember.” The difficulty of this fieldwork is twofold: first, on those mountains, “the trails are not particularly well marked” and second, the frogs are hard to find.

“You can hear them singing and there’s probably hundred of them, but you simply can’t catch them. Because once you get closer, just from the vibration in the ground, they keep silent for 20 minutes or half and hour,” Pie told the BBC. The scientists actually found them by sifting through leaf litter on the forest floor—which is not only careful work but, given that snakes are also common in that area, a somewhat dangerous game.

Brachycephalus verrucosus (Photo: PeerJ, Ribeiro, et al., CC BY 4.0)

Bonus finds: Messages from Stalin-era prison system written in nail polish, ISIS love letter, ANOTHER black widow spider in British supermarket grapes

Every day, we highlight one newly lost or found object, curiosity or wonder. Discover something unusual or amazing? Tell us about it! Send your finds to sarah.laskow@atlasobscura.com.