In a recent discovery, researchers from the Zoological Survey of India (ZSI) and the Andhra Pradesh Biodiversity Board have unveiled new insights into the amphibian diversity of the Eastern Ghats. Their findings shed light on ancient connections between the region and Sri Lanka, dating back approximately 10,000 years.

The researchers identified two amphibian species in the Eastern Ghats, not previously recognized as new species but significant due to their association with Sri Lanka. These discoveries suggest a historical dispersal of frogs between the Indian mainland and Sri Lanka, likely facilitated by a land bridge that existed during a period of fluctuating sea levels and changing monsoon patterns.

Of particular interest is the Sri Lankan golden-backed frog, originally documented in Sri Lanka in 1829. Genetic analysis revealed a close similarity between the frogs found in the Eastern Ghats and their Sri Lankan counterparts, despite a separation of nearly 700 kilometers between their habitats. This species, known for its association with freshwater environments, represents a rediscovery in the Eastern Ghats after nearly two centuries of absence from scientific records in India.

Similarly, the Sri Lankan shrub frog, first identified in Sri Lanka in 2005, has now been found in the Eastern Ghats. This species is notable for its unique reproductive strategy, termed “direct development,” where eggs hatch directly into miniature adults, bypassing the tadpole stage typical of many amphibians.

These findings underscore the biogeographical and evolutionary significance of the Eastern Ghats as a refuge for amphibian species with historical ties to Sri Lanka. Despite morphological variations such as coloration and minor genetic differences, DNA barcoding confirmed the genetic identity of these frogs across both regions.

The discovery adds to the ecological importance of the Eastern Ghats, known to harbor 28 amphibian species. Amphibians are considered vital indicators of ecosystem health, and their presence in the region suggests a robust and pristine environment. In contrast, the Western Ghats of India, despite being more extensively studied, host significantly fewer amphibian species, underscoring the unique biodiversity of the Eastern Ghats.

The researchers emphasized the implications of these findings for understanding historical biogeographic connections and the impacts of past geological events on species distribution. They suggested that the discovery supports theories of amphibian migration during periods of land connectivity between India and Sri Lanka, particularly during the late Pleistocene epoch.

The discovery of these amphibian species in the Eastern Ghats highlights the ongoing importance of biodiversity research and conservation efforts in the region. It underscores the need for continued exploration and protection of habitats that serve as crucial refuges for unique and historically significant species.

Moving forward, the researchers plan to further investigate the ecological roles and conservation status of these newly identified amphibian populations. Their work contributes to a deeper understanding of India’s amphibian diversity and its broader implications for evolutionary biology and conservation science.