In a significant discovery for Indian biodiversity, a team of scientists has identified two entirely new species of slender-armed frogs in the remote mountain ranges of Arunachal Pradesh. The findings, published in the scientific journal PeerJ, highlight the rich, yet underexplored, amphibian life of the northeastern region.
Honoring a Legacy and a Landscape
The research team, led by renowned amphibian expert Professor S D Biju from the University of Delhi, made the discovery as part of the PhD work of student A N Dikshit Akalabya Sarmah. They have bestowed meaningful names upon the new amphibians.
One species has been named Leptobrachium Somani, or Soman's Slender Arm Frog, in honour of the late Kerala-based journalist E Somanath. This tribute recognizes his dedicated environmental reporting and profound love for nature. The frog was located in Tiwari Gaon.
The second species is named Leptobrachium Mechuka, the Mechuka Slender Arm Frog, after the picturesque town of Mechuka in Arunachal Pradesh where it was first found.
Distinctive Features of the New Frogs
Soman's Slender Arm Frog is a small amphibian, measuring about 55mm in length. It sports a uniformly greyish-brown body adorned with irregular light-grey patterns. Its most striking feature is its distinctive silver-grey to light-blue eyes. An inhabitant of evergreen forests, males are often heard calling from stream banks.
The Mechuka Slender Arm Frog is slightly larger, at roughly 60mm long. It has a uniformly brown body with a reddish tinge and captivating silvery-white eyes. This species thrives in evergreen forests and the adjacent grasslands near Mechuka.
The Brahmaputra: A River That Divides Species
The study goes beyond mere description, offering crucial insights into the biogeography of the region. Professor Biju explained that the identification was based on multiple lines of evidence, confirming these frogs as distinct evolutionary lineages.
A key finding is the role of the Brahmaputra River as a significant biogeographical barrier. Both newly discovered species are found only north of the mighty river. In contrast, all other known members of the Leptobrachium genus are confined to areas south of the Brahmaputra. This demonstrates how the river has influenced the geographic distribution and diversification patterns of these frogs over millennia.
Significance for Conservation
The slender-armed frogs belong to the family Megophryidae, a group comprising about 40 species found exclusively in South and Southeast Asia. Each new discovery underscores the incredible biological wealth of Arunachal Pradesh and the Eastern Himalayas, a global biodiversity hotspot.
Finding such distinct species also emphasizes the need for continued exploration and conservation in these fragile ecosystems. The naming of one frog after an environmental journalist serves as a poignant reminder of the vital link between scientific discovery, public awareness, and the protection of our natural heritage.
