100 million year old fish Gollum Snakehead found in Kerala – Burning Issues

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FISH

It looks like a dragon, swims like an eel, and has remained hidden for a hundred million years. After a social media post made a researcher in Kerala curious, a type of fish was discovered in the watery underground rocks of the state that scientists have named “Gollum”, after the dark and conflicted character of JRR Tolkien’s epic saga ‘Lord of the Rings’.
‘Aenigmachanna gollum’ belongs to an old family of fish, called dragon snakeheads, which retains its primitive characteristics after all these millennia.

The discovery of a new family of fish is very rare. The dragon snakeheads have evaded scientists till now because they live in subterranean aquifers and come to the surface only after heavy flooding from rain.
The closest relative of the family Aenigmachannidae is the Channidae, of which at least 50 species can be found in the streams and lakes of Asia and tropical Africa. According to molecular analyses, the two families split from each other 34 million to 109 million years ago.

The lack of evolution can be seen in the shortened swim bladder of the dragon snakeheads as well as fewer vertebrae with ribs. These indicate that the family is less specialised than regular snakeheads. The family also has eyes and a reddish brown pigmentation, which is unusual as most subterranean fish are pale and have no eyes.
Unlike the Channidae, the Aenigmachannidae also lack the suprabranchial organ that allows the former to breathe air and proliferate widely.

It is likely that the Gollum and Mahabali would have remained unknown for longer without the power of social media.
At the beginning of 2018, Rajeev Raghavan, a fish researcher at Kerala University of Fisheries and Ocean Studies and co-author of the present study, saw a post on social media of a curious fish that a person had found in a well in the backyard. He could not recognise the creature and emailed the picture to Britz, who couldn’t understand it either.

Raghavan and his colleagues started to collect more specimens of the fish for a scientific study that would bring Britz all the way to India. Then, in a flooded paddy field in Kochi, Britz would see the elusive fish rise to the surface late one night.
The Gollum snakehead was first identified as a new species and genus in May 2019 in a study published in Zootaxa. Soon after the researchers came across a single specimen of its sister, the Mahabali snakehead.

The researchers say that the area where Aenigmachanna was collected is part of the Western Ghats – Sri Lanka Hotspot — which is among the richest biodiversity hotspots in the world.
Ten other species of subterranean fish have been discovered in the aquifers. This area also services around six million wells in the region so the water table is lowering — a danger to other unknown life forms that have resided here for millennia.