A new family of bony freshwater fish has been discovered from paddy fields of Kerala. It is believed that this fish has lineage going back to Gondwanaland and has survived even after the parting away of the Asian and African continents began some 120 million years ago.
Researchers from the Indian Institute of Science, Education and Research (IISER), Pune, Kerala University of Fisheries and Ocean Studies (KUFOS), Nirmalagiri College in Kerala, Natural History Museums in London and Berne, along with Senckenberg Natural History Collections, Germany, were part of the discovery of the fish family named Aenigmachannidae.
CT scans and detailed analysis of the specimen led the scientific team to trace primitive characteristics, thereby concluding that the fish is a ‘living fossil’.
“It is very rare to discover a new family of fish. What makes this discovery unique is that the fish specimen remains primitive in many ways and has not displayed any evolutionary characteristics,” said Rajeev Raghavan from KUFOS, who was part of the study published in Scientific Reports of Nature on Wednesday.
The fish, with a long and elongated body, was sighted only post sunset along the paddy fields of Mallapuram district in north Kerala last year.
Yet another distinction in the newly discovered fish family was that it has remained subterranean. This, unlike its sister species that have evolved and now thrive in surface water bodies commonly found in west, central Africa regions and Asia.
Even though about 10 enigmatic subterranean fish species are known to be present in Kerala, just how Aenigmachannidae was spotted here remains a mystery. But researchers do not rule out the possibility of depleting groundwater levels in the state, especially following the devastating floods in 2018. This, they say, could have altered the fish behaviour and possibly forced them to migrate into these newer regions like paddy fields and dug wells.
“The aquifers in the state have a wealth of relic fauna. But the subterranean ecosystems are facing threats due to indiscriminate extraction and pollution of groundwater,” co-author Neelesh Dahanukar from IISER, Pune, said.
📣 The Indian Express is now on Telegram. Click here to join our channel (@indianexpress) and stay updated with the latest headlines