Researchers at the University of Kansas have discovered new species of frog found in Mindoro Islands in the Philippines. Scientists first thought that the fanged frog has no difference from the other species, but recognized its distinction because of its unique mating call and key differences in its genome.

In their published findings, the lead author Mark Herr, a doctoral student at the KU Biodiversity Institute and Natural History Museum and Department of Ecology & Evolutionary Biology said, “Scientists for the last 100 years thought that these frogs were just the same species as frogs on a different island in the Philippines because they couldn’t tell them apart physically. We ran a bunch of analyses — and they do indeed look identical to the naked eye — however, they are genetically isolated. We also found differences in their mating calls. They sound quite different. So, it was a case of using acoustics to determine that the species was different, as well as the new genetic information.”
“This is what we call a cryptic species because it was hiding in plain sight in front of biologists, for many, many years,” he said.

KU scientists worked in Mindoro Islands and gathered genetic samples of the locally popular fanged frog, known scientifically as Limnonectes beloncioi (or commonly as the Mindoro Fanged Frog) several years back but did not conduct the study on them until recently. Scientists thought they were the same species as the ones found in the neighboring Palawan Island named Acanth’s Fanged Frog.

“We ran genetic analyses of these frogs using some specific genetic markers, and we used a molecular clock model just to get a very basic estimate [of] how long we thought that these frogs may have been separated from one another,” Herr said. “We found they’re related to each other, they are each other’s close relatives, but we found they’d been separate for two to six million years — it’s a really long time for these frogs. And it’s very interesting that they still look so similar but sound different.”

A KU graduate student who specializes in studying many species of fanged frogs said frog’s fangs are used most likely in the battle to access prime mating sites and to defend themselves against predators. The Mindoro fanged frog, which is a stream frog, is sometimes hunted by people for food.

Sources:
https://www.sciencetimes.com/articles/31026/20210505/mindoro-fanged-frog-amphibians-philippines.htm
https://bioone.org/journals/ichthyology-and-herpetology/volume-109/issue-1/h2020095/A-New-Morphologically-Cryptic-Species-of-Fanged-Frog-Genus-Limnonectes/10.1643/h2020095.full
https://www.newswise.com/articles/meet-the-freaky-fanged-frog-from-the-philippines