Newly recognized Taiwanese endemic frog listed as critically endangered

Taipei, March 21 (CNA) A Taiwanese research team on Thursday announced that a newly recognized species of frog has been listed as critically endangered.

Professor Lin Si-min (林思民) from National Taiwan Normal University's Department of Life Sciences, who led the research team, said the previously unrecognized music frog species, Nidirana shyhhuangi, has now been officially identified and listed as a critically endangered species.

The team's findings were published on Feb. 27 and it was announced that the adult population of the species is estimated to be between 300 and 700.

Lin explained that the species was discovered in Nantou County in 1984 by Chen Shyh-huang (陳世煌), but that because the frog had a similar morphology to the Nidirana okinavana, also known as the harpist brown frog -- native to Okinawa, Japan-- it was not formally classified as a species endemic to Taiwan.

However, using molecular, morphological and acoustic analysis, Lin's research team, which began studying the species in 2019, found enough differences between the Taiwanese and Japanese populations to support identifying the Taiwan frog as a distinct species.

Lin's team said in 2023 that the Taiwanese frog has a "significantly smaller and non-overlapping body size, relatively longer forelimbs and hindlimbs, smaller internostril and interorbital distances, with a higher number of cross bands on thigh and shank," compared to the Japanese frog.

Acoustic analysis in 2024 found that the Taiwan frog "produces calls with a rapid tempo and higher pulse number, with a higher dominant frequency than the Japanese clade."

Lin's team decided to name the breed Nidirana shyhhuangi -- after Chen's first name Shyh-huang.

The team also said that the endemic frog is critically endangered due to its limited habitat, which is confined to the Lotus Pond Park area in Nantou and the Xiangshan area near Sun Moon Lake. The frog's mud nests occupy a total wetland area of just 0.015 square kilometers.

The species faces multiple threats, including natural disasters such as typhoons and mudslides as well as overdevelopment.

This led to the Taiwan genus being listed as critically endangered on Taiwan's Red List of threatened species.

For the sake of preserving the Nidirana shyhhuangi, Taiwan Biodiversity Research Institute associate research fellow Lin Chun-fu (林春富) said his organization, and the Taiwan Forestry Research Institute, which also contributed to the research, have come up with plans including long-term monitoring and relocation conservation to protect the species.

The Forestry and Nature Conservation Agency will also address garbage and litter around the frogs' mud nests alongside programs to properly channel water into the wetland habitats to better protect the endemic species.