A random TikTok video helped scientists discover a rare underground fish in India

A TikTok video usually leads to a new recipe or a dance trend. This one led researchers straight to a brand-new species of fish.

Scientists have discovered a new genus and species of underground earthworm eel living beneath the Indo-Gangetic Plain in Bihar, northern India. Named Gangaichthys indonepalicus, it’s the first subterranean eel ever recorded from the Gangetic Basin, and it all started with a random borewell (drilled well) video.

The study was published in ZooKeys and led by an international team from the Thackeray Wildlife Foundation, Shivaji University, the Shanghai Synchrotron Radiation Facility, and the Zoological Survey of India. Back in 2024, someone posted a short clip on TikTok showing a strange, tiny fish coming out of a water borewell near the India-Nepal border, and that was enough to catch researchers’ attention.

“The unique morphology of the fish in the video, and the fact that there are no known stygobitic fish from the region, motivated us to track down the species to ascertain its identity,” the team said.

How researchers discovered the underground fish?

Researcher Akshay Khandekar and his team had to manually pump thousands of liters of water out of borewells in Bihar, after tracking down owners willing to let them try. The first fish that came up had already been damaged in the process and didn’t survive. The team’s actual holotype specimen only showed up after they pumped out another 500 liters.

What makes this fish so unusual?

At just about four centimeters long, Gangaichthys indonepalicus is built for a life with zero sunlight. It has skin-covered eyes, a see-through unpigmented body, and no ribs at all. CT scans and genetic testing confirmed it’s not just a new species, but an entirely new genus within the Chaudhuriidae family.

The name itself is a tribute. “Gangaichthys means fish of the Ganga,” explained researcher Agarwal, tying the species to the river that shapes life across the region. Researcher Tejas Thackeray added that “indonepalicus” nods to where the fish was found, right along the India-Nepal border.

Discoveries like this are a reminder of how little we still know about what’s hiding beneath our feet.