There are millions of undiscovered species on Earth. In fact, by some estimates, nearly 90 percent of life on our planet hasn’t been formally described by science. Some of these unknown creatures are very small, like insects, others live in hard-to-reach areas, and many are hiding in plain sight. None of them have any kind of social media presence to speak of—except for one: A previously unknown (to scientists) species of blind cavefish that was recently discovered after being caught on TikTok.
In the short clip, which hit the social media platform in 2024, the species appeared tiny and pale, and seemed to have emerged from a borewell near the border of India and Nepal. So researchers from the Thackeray Wildlife Foundation set out to find it—a job that proved to be an arduous task.
“Procuring samples of this unusual fish was challenging,” study author Akshay Khandekar of the Thackeray Wildlife Foundation explained in a statement. “Identifying potential handpumps (borewells) and wells, and obtaining permission from their owners to extract water for the purpose of searching for the fish proved difficult. This became more intensive when we finally began manually pumping water.”
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And that’s something of an understatement. They found their first little fish after pumping more than 525 gallons of water, but it suffered damage on its way out, so they had to keep pumping. More than 130 gallons later, they had a pristine new specimen, what would become the holotype (that is, the single representative) to describe the species.
The wriggling fish was around an inch and a half long, had reduced eyes covered in skin, and lacked ribs. According to the team’s genetic analysis, it was a new member of the family Chaudhuriidae, the aptly named earthworm eels. In a study describing the species, the team dubbed their find Gangaichthys indonepalicus.
It’s the first stygobitic (underwater cave-dwelling) fish found in the area, but it’s not the only recently discovered stygobitic fish. Just last month, researchers from Auburn University announced the discovery of Demogorgonichthys arcanus (named after the demogorgon from Stranger Things) in Bobcat Cave. Located on an Army base in Huntsville, Alabama, the cave system is also home to the endangered Alabama Cave Shrimp, so it’s been extensively studied.
“There is still so much we do not know about our own environment,” study author Jonathan Armbruster said in a statement. “For something new to show up in a place this well studied is rare. This was the right person, at the right time, able to notice that it was something different.”
Two species down and millions upon millions more to go. 
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Lead image: Ishan Agarwal
