‘Rattling’ sound leads scientists to ‘floating’ creature — a new species — in Vietnam

"Krrrrr… kkrrrrr… kkrrrrr."

The "rattling" sound drifted through the darkened Vietnam forest and into the ears of several scientists. Curious, they followed the call to its source — a "floating" creature — and discovered a new species.

Researchers were surveying the Song Hinh protected forest in Phú Yên province at night when they heard the "ratchet"-like sound, according to a study published May 26 in the journal Zoological Research.

They followed the noise to a puddle on a forest road, researchers said in a supplemental study. Bathed in the red glow of their headlamps, they spotted several frogs "floating" in the water and others "hiding under the leaves" nearby.

Disturbed, the animals jumped into the water, researchers said. They didn't get very far, however, as researchers collected three specimens.

Looking closer, researchers noticed the frogs were "clearly" different than any spotted before — and discovered a new species, the study said.

The new species was named Nanohyla albopunctata, or the Song Hinh pygmy narrow-mouthed frog, the study said. Reaching only about 0.8 inches in size, the frog has a dark brown and orange coloring.

On its back, the Song Hinh pygmy narrow-mouthed frog has a "distinctly darker reddish-brown ‘teddy-bear’-shaped" marking, researchers said.

The animal looks almost spray painted but matches the brown ground, photos show.

The new species was identified as distinct based on its morphology, especially the white spots on its head, the study said. Researchers named the frog after those white spots, with "albopunctata" meaning "white-spotted" in Latin, the study said.

DNA analysis also confirmed the new species had a "significant level of genetic distinctiveness," the study said. Among frogs, species are considered distinct if they have more than 3% genetic divergence.

The Song Hinh pygmy narrow-mouthed frog had about 5% genetic divergence from its closest relative and over 9% divergence from its furthest relative, according to researchers.

The Song Hinh protected forest is an "evergreen tropical forest," the study said. Because of its "unique environmental conditions" and native species, researchers called for "additional conservation" of the forest.

"Today, habitat loss is considered one of the greatest threats to amphibians in Southeast Asia, particularly Vietnam," the study said.

The research team included Vladislav Gorin, Alexey Trofimets, Svetlana Gogoleva, Le Xuan Dac and Nikolay Poyarkov.

Phú Yên, a province along the southern coast, is about 285 miles northeast of Ho Chi Minh City.

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