Creature discovered near waterfall on perilous island mountain is a new species
In 1991, researchers made an “extremely steep and rugged” trek up one of Papua New Guinea’s tallest mountains to survey wildlife in this rarely seen and poorly understood landscape.
As they scoured the area, researchers turned over several rocks in the “splash zone” of a waterfall on Mount Capella in the Star Mountains to reveal several unusual frogs, according to a study published July 15 in the peer-reviewed journal Zootaxa.
They collected three specimens and continued with their work. Despite days and nights of searching the surrounding forest and shallow pools — all while avoiding dangerous hidden sinkholes — the frogs were found nowhere else except the stream at the base of the waterfall, researchers said.
Now, nearly 35 years after the creatures were discovered, researchers have confirmed the frogs represent a new species called Litoria stellarum, or the Star Mountains torrent tree frog.
The new species is described as being medium-sized at just over an inch and a half, with a “robust” body and long toes that extend into a disc-shape at their tips. Its body is mostly brown with patches of light green. It also has silver irises flecked with brown, researchers said.
Based on the species’ size, snout shape, “reduced webbing on hands, and ecology,” researchers said they are confident the new species is closely related to other local stream-breeding Litoria species, particularly Litoria becki.
The Star Mountains torrent tree frog is the third species of frog found only in the very limited “microhabitat” in “the high elevations in the Star Mountains,” according to researchers.
The Star Mountains torrent tree frog was discovered near the Dokfuma Meadow, a “boggy” alpine meadow dominated by ferns, moss mounds and wet mossy alpine forests, according to the study.
The new species is adapted to cold conditions, with temperatures at the time of its discovery ranging between 33 and 64 degrees Fahrenheit.
In New Guinea, areas roughly 10,000 feet above seal level “are typically not suitable for agriculture and are sparsely inhabited, so direct habitat loss is unlikely to be a major threat,” researchers said.
However, as the global climate warms, mountain species that have adjusted to colder temperatures will eventually run out of “upslope” habitat to migrate to as their old environments become uninhabitable, researchers said.
Researchers said additional study is needed to better understand the species’ ecology and potential threats in order to estimate its conservation status. It is currently listed as “data deficient” on the International Union for Conservation of Nature’s Red List, according to the study.
Additional field studies, however, may prove difficult, according to researchers. “It is unlikely that this remote region will be accessible again in the near future because there are no roads or airstrips in the vicinity.”
The Star Mountains are on the western border of Papua New Guinea.
The research team included Stephen J. Richards, Gregory R. Johnston and Paul M. Oliver.
This story was originally published July 21, 2025 at 6:09 PM with the headline "Creature discovered near waterfall on perilous island mountain is a new species."
