Indian scientists discover two new frog species in Arunachal Pradesh

New Delhi: After months of extensive field work, Indian scientists have found two new slender-armed frogs from their secretive habitats in Arunachal Pradesh and named one of them after a journalist.

Delhi University frog hunter S D Biju and his PhD student Akalabya, spotted the new species north of Brahmaputra river following three years of expeditions to isolated mountain regions of Arunachal Pradesh.

One of them, Soman’s Slender Arm Frog (Leptobrachium somani), was discovered at Tiwari Gaon in Arunachal Pradesh and named after late E Somanath, a noted journalist from Kerala in recognition of his dedicated reporting on environmental issues and his deep love for nature.

Leptobrachium somani is a small-sized frog, measuring approximately 55 mm in length, with a uniformly greyish-brown body marked by irregular light-grey patterns and distinctive silver-grey to light-blue eyes.

An evergreen forest species, males are typically found calling from the banks of fast- or slow-flowing streams.

Mechuka Slender Arm Frog.

The second new species, Mechuka Slender Arm Frog (Leptobrachium mechuka), is a small-sized frog measuring about 60 mm in length and found in evergreen forests and adjacent grasslands.

It is named after Mechuka, a small Arunachal Pradesh town close to the China border where it was first collected. It has a uniformly brown body with a reddish tinge and distinctive silvery-white eyes.

Brahmaputra river acted as the biogeographical barrier for these frogs aiding species diversification. While these two species are found in the north of the river, all other members of the genus are confined to its southern side.

Arunachal Pradesh is a part of the Himalaya biodiversity hotspot, one of the world’s most biologically rich regions, harbouring exceptional plant and animal diversity found nowhere else on Earth, including a wide variety of amphibians.

Among these amphibians are members of the family Megophryidae, one of the most diverse frog families globally with 366 recognised species, including the Asian horned frogs.

The slender-armed frogs (Leptobrachium), belonging to this family, comprise around 40 species and are known only from South and Southeast Asia.

In their fieldwork across five northeastern states, the researchers documented several populations of slender armed frogs

Subsequent laboratory analyses confirmed that the frogs from Arunachal Pradesh represented new species.

“The descriptions of the new species are based on multiple lines of evidence, confirming that they represent distinct evolutionary lineages,” Biju said.

The study was published on Friday in the US based scientific journal Peer J.