A newfound, pea-size frog, Microhyla nepenthicola, sits on the tip of a pencil.
One of the smallest frogs in the world, the species was spotted inside and around pitcher plants in Malaysian rain forests on the island of Borneo (map), which is divided among Brunei, Indonesia, and Malaysia.
The new species was announced Wednesday, but the frogs have been hiding in plain view for more than a century.
"I saw some specimens in museum collections that are over a hundred years old," co-discoverer Indraneil Das said in a statement.
"Scientists presumably thought they were juveniles of other species," said Das, a herpetologist at Universiti Malaysia Sarawak in Malaysia. "But it turns out they are adults of this newly discovered microspecies."
Das, the co-discoverer of the new Bornean micro-frog, will join Moore in Indonesia in September to search for the Sambas stream toad (picture), last seen in the 1950s.
Photograph courtesy Indraneil Das, Institute of Biodiversity and Environmental Conservation
The new pea-size frog gets its name from the plant that the amphibian depends on to survive, Nepenthes ampullaria, which has a globular pitcher and grows in damp, shady forests.
At dusk, male frogs typically gather around a pitcher plant and sing a "love song" for females: raspy, minutes-long serenades separated by brief silences. This frog symphony can go on for several hours, Moore said.
It was the frog's croak that convinced scientists they were dealing with a new species, and not a juvenile of another species. That's because only adult frogs can sing, Moore said.