ZSI research strengthens biogeographic links between India and Sri Lanka

Kolkata: In a recent breakthrough, scientists from Zoological Survey of India (ZSI) and a group of professors from South Korea have collaboratively uncovered compelling genetic evidence linking the snakehead fish populations across Peninsular India and Sri Lanka. The findings, published in the prestigious Molecular Biology Reports journal by Springer Nature, offer new insights into the biogeography and evolutionary history of this lesser-known freshwater species, ‘Channa kelaartii’.

The study, led by Boni Amin Laskar from the High-Altitude Regional Centre of the ZSI (Solan in Himachal Pradesh) identified the species, ‘Channa kelaartii’, in the Eastern Ghats of peninsular India, raising questions about its distribution and evolutionary past. “This discovery challenges our understanding of the species’ range of distribution,” said Laskar. “We observed striking morphological similarities between the Indian and Sri Lankan populations and our molecular data, based on mitochondrial gene analysis, confirms this relationship,” he added. Laskar and his team demonstrated 13 haplotypes between the two regions, with low intra-regional genetic divergence, suggesting a shared evolutionary lineage.

Interestingly, a haplotype from the Western Ghats of India showed only 0.17 per cent genetic divergence from Sri Lankan samples, evidencing potential biogeographical connectivity.

Shantanu Kundu, the corresponding author from Pukyong National University, South Korea, highlighted the ancient biogeographic connections that may explain these findings.

“The genetic similarities suggest that freshwater species like Channa kelaartii may have maintained gene flow across the Palk Isthmus during the Plio-Pleistocene, when land bridges or freshwater pathways connected India and Sri Lanka.”

Prior to this study, the genetic diversity of Eastern Ghats channids, particularly C. kelaartii, remained ambiguous.

Dhriti Banerjee, Director of ZSI stated: “The combination of conventional taxonomic study and modern genetic analysis can be incredibly powerful in unraveling complex biogeographical mysteries.”

She further called for more detailed genetic studies to unveil the mechanisms driving genetic differentiation, dispersal and ecological adaptation in fish within freshwater environments.