Seven new species of the miniature frog genus Brachycephalus have been discovered in the Atlantic rainforest of Brazil.

Strangely, researchers found that the species live in separate areas, and a number of factors force them to stay on their own distinct mountain tops. This separation means that the members of the genus have become a number of different species, writes Rachel Feltman for The Washington Post.

Scientists Find 7 New Species Of Mini Frogs In Brazil

Tiny frogs have fewer fingers and toes than larger cousins

The miniature frogs generally measure less than a centimeter in length, and are described in a paper which can be found on PeerJ. The seven species are differentiated by their skin color and texture, as well as the production of varying levels of a neurotoxin called tetrodoxin.

The vivid color of their skin are designed to warn off predators, and a number of the species have fewer fingers and toes than most other frogs because of their small size.

Researcher Marco Pie of the Federal University of Parana and his colleagues explored a series of small, rugged mountains in order to find the frogs on their specific mountain tops. Although each mountain top is expected to be home to a new species, it is no easy task spotting a miniature frog which measures less than a centimeter in length.

Other species may still be discovered

“It takes a lot of practice and sometimes it’s very frustrating, to go up the mountain for many hours and come back empty-handed,” Pie said during an interview with BBC. “You can hear them singing and there’s probably hundreds 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, say, 20 minutes or half an hour. And then you have to go through the leaf litter very carefully with your hands,” he said.

The researchers claim that the frogs are in danger due to the exclusivity of their habitats. They are under threat from logging and climate change, which is a particular danger because the frogs are sensitive to changes in temperature. The reason that they stay on the mountain tops is to avoid the higher temperatures of the forest below.

The team recommends that the frogs may need to be raised in captivity to ensure the survival of the various species, and the clock is ticking in the race to discover the rest of the species.